diff --git a/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go.tmpl b/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go.tmpl
index 18726e7b..dc108466 100644
--- a/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go.tmpl
+++ b/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go.tmpl
@@ -72,8 +72,9 @@ type ActiveDirectoryIdentityProviderGroupSearchAttributes struct {
 type ActiveDirectoryIdentityProviderUserSearch struct {
 	// Base is the dn (distinguished name) that should be used as the search base when searching for users.
 	// E.g. "ou=users,dc=example,dc=com".
-	// Optional, when not specified it will be defaulted based on the host, for example if your active directory host is
-	// "activedirectory.example.com:636", it will be "dc=activedirectory,dc=example,dc=com".
+	// Optional, when not specified it will search the whole directory tree.
+	// Note that if your bind user only has permission to search a subtree, this must be specified.
+	// Search a subtree will also be faster.
 	// +optional
 	Base string `json:"base,omitempty"`
 
diff --git a/cmd/pinniped/cmd/kubeconfig.go b/cmd/pinniped/cmd/kubeconfig.go
index 54042b34..7eb70031 100644
--- a/cmd/pinniped/cmd/kubeconfig.go
+++ b/cmd/pinniped/cmd/kubeconfig.go
@@ -153,7 +153,7 @@ func kubeconfigCommand(deps kubeconfigDeps) *cobra.Command {
 	f.BoolVar(&flags.oidc.debugSessionCache, "oidc-debug-session-cache", false, "Print debug logs related to the OpenID Connect session cache")
 	f.StringVar(&flags.oidc.requestAudience, "oidc-request-audience", "", "Request a token with an alternate audience using RFC8693 token exchange")
 	f.StringVar(&flags.oidc.upstreamIDPName, "upstream-identity-provider-name", "", "The name of the upstream identity provider used during login with a Supervisor")
-	f.StringVar(&flags.oidc.upstreamIDPType, "upstream-identity-provider-type", "", "The type of the upstream identity provider used during login with a Supervisor (e.g. 'oidc', 'ldap')")
+	f.StringVar(&flags.oidc.upstreamIDPType, "upstream-identity-provider-type", "", "The type of the upstream identity provider used during login with a Supervisor (e.g. 'oidc', 'ldap', 'activedirectory')")
 	f.StringVar(&flags.kubeconfigPath, "kubeconfig", os.Getenv("KUBECONFIG"), "Path to kubeconfig file")
 	f.StringVar(&flags.kubeconfigContextOverride, "kubeconfig-context", "", "Kubeconfig context name (default: current active context)")
 	f.BoolVar(&flags.skipValidate, "skip-validation", false, "Skip final validation of the kubeconfig (default: false)")
diff --git a/cmd/pinniped/cmd/kubeconfig_test.go b/cmd/pinniped/cmd/kubeconfig_test.go
index cb9f7b83..464271b3 100644
--- a/cmd/pinniped/cmd/kubeconfig_test.go
+++ b/cmd/pinniped/cmd/kubeconfig_test.go
@@ -150,7 +150,7 @@ func TestGetKubeconfig(t *testing.T) {
 				      --static-token-env string                  Instead of doing an OIDC-based login, read a static token from the environment
 				      --timeout duration                         Timeout for autodiscovery and validation (default 10m0s)
 				      --upstream-identity-provider-name string   The name of the upstream identity provider used during login with a Supervisor
-				      --upstream-identity-provider-type string   The type of the upstream identity provider used during login with a Supervisor (e.g. 'oidc', 'ldap')
+				      --upstream-identity-provider-type string   The type of the upstream identity provider used during login with a Supervisor (e.g. 'oidc', 'ldap', 'activedirectory')
 			`)
 			},
 		},
diff --git a/cmd/pinniped/cmd/login_oidc.go b/cmd/pinniped/cmd/login_oidc.go
index 9141d26a..c1d2c321 100644
--- a/cmd/pinniped/cmd/login_oidc.go
+++ b/cmd/pinniped/cmd/login_oidc.go
@@ -107,7 +107,7 @@ func oidcLoginCommand(deps oidcLoginCommandDeps) *cobra.Command {
 	cmd.Flags().StringVar(&flags.conciergeAPIGroupSuffix, "concierge-api-group-suffix", groupsuffix.PinnipedDefaultSuffix, "Concierge API group suffix")
 	cmd.Flags().StringVar(&flags.credentialCachePath, "credential-cache", filepath.Join(mustGetConfigDir(), "credentials.yaml"), "Path to cluster-specific credentials cache (\"\" disables the cache)")
 	cmd.Flags().StringVar(&flags.upstreamIdentityProviderName, "upstream-identity-provider-name", "", "The name of the upstream identity provider used during login with a Supervisor")
-	cmd.Flags().StringVar(&flags.upstreamIdentityProviderType, "upstream-identity-provider-type", "oidc", "The type of the upstream identity provider used during login with a Supervisor (e.g. 'oidc', 'ldap')")
+	cmd.Flags().StringVar(&flags.upstreamIdentityProviderType, "upstream-identity-provider-type", "oidc", "The type of the upstream identity provider used during login with a Supervisor (e.g. 'oidc', 'ldap', 'activedirectory')")
 
 	// --skip-listen is mainly needed for testing. We'll leave it hidden until we have a non-testing use case.
 	mustMarkHidden(cmd, "skip-listen")
@@ -165,10 +165,12 @@ func runOIDCLogin(cmd *cobra.Command, deps oidcLoginCommandDeps, flags oidcLogin
 		// this is the default, so don't need to do anything
 	case "ldap":
 		opts = append(opts, oidcclient.WithCLISendingCredentials())
+	case "activedirectory":
+		opts = append(opts, oidcclient.WithCLISendingCredentials())
 	default:
 		// Surprisingly cobra does not support this kind of flag validation. See https://github.com/spf13/pflag/issues/236
 		return fmt.Errorf(
-			"--upstream-identity-provider-type value not recognized: %s (supported values: oidc, ldap)",
+			"--upstream-identity-provider-type value not recognized: %s (supported values: oidc, ldap, activedirectory)",
 			flags.upstreamIdentityProviderType)
 	}
 
diff --git a/cmd/pinniped/cmd/login_oidc_test.go b/cmd/pinniped/cmd/login_oidc_test.go
index 055dcec6..e888599e 100644
--- a/cmd/pinniped/cmd/login_oidc_test.go
+++ b/cmd/pinniped/cmd/login_oidc_test.go
@@ -78,7 +78,7 @@ func TestLoginOIDCCommand(t *testing.T) {
 				      --session-cache string                     Path to session cache file (default "` + cfgDir + `/sessions.yaml")
 				      --skip-browser                             Skip opening the browser (just print the URL)
 					  --upstream-identity-provider-name string   The name of the upstream identity provider used during login with a Supervisor
-					  --upstream-identity-provider-type string   The type of the upstream identity provider used during login with a Supervisor (e.g. 'oidc', 'ldap') (default "oidc")
+					  --upstream-identity-provider-type string   The type of the upstream identity provider used during login with a Supervisor (e.g. 'oidc', 'ldap', 'activedirectory') (default "oidc")
 			`),
 		},
 		{
@@ -148,7 +148,7 @@ func TestLoginOIDCCommand(t *testing.T) {
 			},
 			wantError: true,
 			wantStderr: here.Doc(`
-				Error: --upstream-identity-provider-type value not recognized: invalid (supported values: oidc, ldap)
+				Error: --upstream-identity-provider-type value not recognized: invalid (supported values: oidc, ldap, activedirectory)
 			`),
 		},
 		{
@@ -173,6 +173,17 @@ func TestLoginOIDCCommand(t *testing.T) {
 			wantOptionsCount: 5,
 			wantStdout:       `{"kind":"ExecCredential","apiVersion":"client.authentication.k8s.io/v1beta1","spec":{},"status":{"expirationTimestamp":"3020-10-12T13:14:15Z","token":"test-id-token"}}` + "\n",
 		},
+		{
+			name: "activedirectory upstream type is allowed",
+			args: []string{
+				"--issuer", "test-issuer",
+				"--client-id", "test-client-id",
+				"--upstream-identity-provider-type", "activedirectory",
+				"--credential-cache", "", // must specify --credential-cache or else the cache file on disk causes test pollution
+			},
+			wantOptionsCount: 5,
+			wantStdout:       `{"kind":"ExecCredential","apiVersion":"client.authentication.k8s.io/v1beta1","spec":{},"status":{"expirationTimestamp":"3020-10-12T13:14:15Z","token":"test-id-token"}}` + "\n",
+		},
 		{
 			name: "login error",
 			args: []string{
diff --git a/deploy/supervisor/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml b/deploy/supervisor/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml
index 03fbcd08..0f94c50a 100644
--- a/deploy/supervisor/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml
+++ b/deploy/supervisor/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml
@@ -155,9 +155,10 @@ spec:
                   base:
                     description: Base is the dn (distinguished name) that should be
                       used as the search base when searching for users. E.g. "ou=users,dc=example,dc=com".
-                      Optional, when not specified it will be defaulted based on the
-                      host, for example if your active directory host is "activedirectory.example.com:636",
-                      it will be "dc=activedirectory,dc=example,dc=com".
+                      Optional, when not specified it will search the whole directory
+                      tree. Note that if your bind user only has permission to search
+                      a subtree, this must be specified. Search a subtree will also
+                      be faster.
                     type: string
                   filter:
                     description: Filter is the ActiveDirectory search filter which
diff --git a/generated/1.17/README.adoc b/generated/1.17/README.adoc
index d0ba80df..288c802d 100644
--- a/generated/1.17/README.adoc
+++ b/generated/1.17/README.adoc
@@ -875,7 +875,7 @@ Status of an Active Directory identity provider.
 [cols="25a,75a", options="header"]
 |===
 | Field | Description
-| *`base`* __string__ | Base is the dn (distinguished name) that should be used as the search base when searching for users. E.g. "ou=users,dc=example,dc=com". Optional, when not specified it will be defaulted based on the host, for example if your active directory host is "activedirectory.example.com:636", it will be "dc=activedirectory,dc=example,dc=com".
+| *`base`* __string__ | Base is the dn (distinguished name) that should be used as the search base when searching for users. E.g. "ou=users,dc=example,dc=com". Optional, when not specified it will search the whole directory tree. Note that if your bind user only has permission to search a subtree, this must be specified. Search a subtree will also be faster.
 | *`filter`* __string__ | Filter is the ActiveDirectory search filter which should be applied when searching for users. The pattern "{}" must occur in the filter at least once and will be dynamically replaced by the username for which the search is being run. E.g. "mail={}" or "&(objectClass=person)(uid={})". For more information about ActiveDirectory filters, see https://ldap.com/ldap-filters. Note that the dn (distinguished name) is not an attribute of an entry, so "dn={}" cannot be used. Optional. When not specified, the default will act as if the Filter were specified as the value from Attributes.Username appended by "={}". When the Attributes.Username is set to "dn" then the Filter must be explicitly specified, since the default value of "dn={}" would not work.
 | *`attributes`* __xref:{anchor_prefix}-go-pinniped-dev-generated-1-17-apis-supervisor-idp-v1alpha1-activedirectoryidentityproviderusersearchattributes[$$ActiveDirectoryIdentityProviderUserSearchAttributes$$]__ | Attributes specifies how the user's information should be read from the ActiveDirectory entry which was found as the result of the user search.
 |===
diff --git a/generated/1.17/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go b/generated/1.17/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go
index 18726e7b..dc108466 100644
--- a/generated/1.17/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go
+++ b/generated/1.17/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go
@@ -72,8 +72,9 @@ type ActiveDirectoryIdentityProviderGroupSearchAttributes struct {
 type ActiveDirectoryIdentityProviderUserSearch struct {
 	// Base is the dn (distinguished name) that should be used as the search base when searching for users.
 	// E.g. "ou=users,dc=example,dc=com".
-	// Optional, when not specified it will be defaulted based on the host, for example if your active directory host is
-	// "activedirectory.example.com:636", it will be "dc=activedirectory,dc=example,dc=com".
+	// Optional, when not specified it will search the whole directory tree.
+	// Note that if your bind user only has permission to search a subtree, this must be specified.
+	// Search a subtree will also be faster.
 	// +optional
 	Base string `json:"base,omitempty"`
 
diff --git a/generated/1.17/crds/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml b/generated/1.17/crds/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml
index 03fbcd08..0f94c50a 100644
--- a/generated/1.17/crds/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml
+++ b/generated/1.17/crds/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml
@@ -155,9 +155,10 @@ spec:
                   base:
                     description: Base is the dn (distinguished name) that should be
                       used as the search base when searching for users. E.g. "ou=users,dc=example,dc=com".
-                      Optional, when not specified it will be defaulted based on the
-                      host, for example if your active directory host is "activedirectory.example.com:636",
-                      it will be "dc=activedirectory,dc=example,dc=com".
+                      Optional, when not specified it will search the whole directory
+                      tree. Note that if your bind user only has permission to search
+                      a subtree, this must be specified. Search a subtree will also
+                      be faster.
                     type: string
                   filter:
                     description: Filter is the ActiveDirectory search filter which
diff --git a/generated/1.18/README.adoc b/generated/1.18/README.adoc
index 12946f74..8d99ecc4 100644
--- a/generated/1.18/README.adoc
+++ b/generated/1.18/README.adoc
@@ -875,7 +875,7 @@ Status of an Active Directory identity provider.
 [cols="25a,75a", options="header"]
 |===
 | Field | Description
-| *`base`* __string__ | Base is the dn (distinguished name) that should be used as the search base when searching for users. E.g. "ou=users,dc=example,dc=com". Optional, when not specified it will be defaulted based on the host, for example if your active directory host is "activedirectory.example.com:636", it will be "dc=activedirectory,dc=example,dc=com".
+| *`base`* __string__ | Base is the dn (distinguished name) that should be used as the search base when searching for users. E.g. "ou=users,dc=example,dc=com". Optional, when not specified it will search the whole directory tree. Note that if your bind user only has permission to search a subtree, this must be specified. Search a subtree will also be faster.
 | *`filter`* __string__ | Filter is the ActiveDirectory search filter which should be applied when searching for users. The pattern "{}" must occur in the filter at least once and will be dynamically replaced by the username for which the search is being run. E.g. "mail={}" or "&(objectClass=person)(uid={})". For more information about ActiveDirectory filters, see https://ldap.com/ldap-filters. Note that the dn (distinguished name) is not an attribute of an entry, so "dn={}" cannot be used. Optional. When not specified, the default will act as if the Filter were specified as the value from Attributes.Username appended by "={}". When the Attributes.Username is set to "dn" then the Filter must be explicitly specified, since the default value of "dn={}" would not work.
 | *`attributes`* __xref:{anchor_prefix}-go-pinniped-dev-generated-1-18-apis-supervisor-idp-v1alpha1-activedirectoryidentityproviderusersearchattributes[$$ActiveDirectoryIdentityProviderUserSearchAttributes$$]__ | Attributes specifies how the user's information should be read from the ActiveDirectory entry which was found as the result of the user search.
 |===
diff --git a/generated/1.18/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go b/generated/1.18/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go
index 18726e7b..dc108466 100644
--- a/generated/1.18/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go
+++ b/generated/1.18/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go
@@ -72,8 +72,9 @@ type ActiveDirectoryIdentityProviderGroupSearchAttributes struct {
 type ActiveDirectoryIdentityProviderUserSearch struct {
 	// Base is the dn (distinguished name) that should be used as the search base when searching for users.
 	// E.g. "ou=users,dc=example,dc=com".
-	// Optional, when not specified it will be defaulted based on the host, for example if your active directory host is
-	// "activedirectory.example.com:636", it will be "dc=activedirectory,dc=example,dc=com".
+	// Optional, when not specified it will search the whole directory tree.
+	// Note that if your bind user only has permission to search a subtree, this must be specified.
+	// Search a subtree will also be faster.
 	// +optional
 	Base string `json:"base,omitempty"`
 
diff --git a/generated/1.18/crds/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml b/generated/1.18/crds/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml
index 03fbcd08..0f94c50a 100644
--- a/generated/1.18/crds/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml
+++ b/generated/1.18/crds/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml
@@ -155,9 +155,10 @@ spec:
                   base:
                     description: Base is the dn (distinguished name) that should be
                       used as the search base when searching for users. E.g. "ou=users,dc=example,dc=com".
-                      Optional, when not specified it will be defaulted based on the
-                      host, for example if your active directory host is "activedirectory.example.com:636",
-                      it will be "dc=activedirectory,dc=example,dc=com".
+                      Optional, when not specified it will search the whole directory
+                      tree. Note that if your bind user only has permission to search
+                      a subtree, this must be specified. Search a subtree will also
+                      be faster.
                     type: string
                   filter:
                     description: Filter is the ActiveDirectory search filter which
diff --git a/generated/1.19/README.adoc b/generated/1.19/README.adoc
index eadb1b33..e999bf69 100644
--- a/generated/1.19/README.adoc
+++ b/generated/1.19/README.adoc
@@ -875,7 +875,7 @@ Status of an Active Directory identity provider.
 [cols="25a,75a", options="header"]
 |===
 | Field | Description
-| *`base`* __string__ | Base is the dn (distinguished name) that should be used as the search base when searching for users. E.g. "ou=users,dc=example,dc=com". Optional, when not specified it will be defaulted based on the host, for example if your active directory host is "activedirectory.example.com:636", it will be "dc=activedirectory,dc=example,dc=com".
+| *`base`* __string__ | Base is the dn (distinguished name) that should be used as the search base when searching for users. E.g. "ou=users,dc=example,dc=com". Optional, when not specified it will search the whole directory tree. Note that if your bind user only has permission to search a subtree, this must be specified. Search a subtree will also be faster.
 | *`filter`* __string__ | Filter is the ActiveDirectory search filter which should be applied when searching for users. The pattern "{}" must occur in the filter at least once and will be dynamically replaced by the username for which the search is being run. E.g. "mail={}" or "&(objectClass=person)(uid={})". For more information about ActiveDirectory filters, see https://ldap.com/ldap-filters. Note that the dn (distinguished name) is not an attribute of an entry, so "dn={}" cannot be used. Optional. When not specified, the default will act as if the Filter were specified as the value from Attributes.Username appended by "={}". When the Attributes.Username is set to "dn" then the Filter must be explicitly specified, since the default value of "dn={}" would not work.
 | *`attributes`* __xref:{anchor_prefix}-go-pinniped-dev-generated-1-19-apis-supervisor-idp-v1alpha1-activedirectoryidentityproviderusersearchattributes[$$ActiveDirectoryIdentityProviderUserSearchAttributes$$]__ | Attributes specifies how the user's information should be read from the ActiveDirectory entry which was found as the result of the user search.
 |===
diff --git a/generated/1.19/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go b/generated/1.19/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go
index 18726e7b..dc108466 100644
--- a/generated/1.19/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go
+++ b/generated/1.19/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go
@@ -72,8 +72,9 @@ type ActiveDirectoryIdentityProviderGroupSearchAttributes struct {
 type ActiveDirectoryIdentityProviderUserSearch struct {
 	// Base is the dn (distinguished name) that should be used as the search base when searching for users.
 	// E.g. "ou=users,dc=example,dc=com".
-	// Optional, when not specified it will be defaulted based on the host, for example if your active directory host is
-	// "activedirectory.example.com:636", it will be "dc=activedirectory,dc=example,dc=com".
+	// Optional, when not specified it will search the whole directory tree.
+	// Note that if your bind user only has permission to search a subtree, this must be specified.
+	// Search a subtree will also be faster.
 	// +optional
 	Base string `json:"base,omitempty"`
 
diff --git a/generated/1.19/crds/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml b/generated/1.19/crds/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml
index 03fbcd08..0f94c50a 100644
--- a/generated/1.19/crds/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml
+++ b/generated/1.19/crds/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml
@@ -155,9 +155,10 @@ spec:
                   base:
                     description: Base is the dn (distinguished name) that should be
                       used as the search base when searching for users. E.g. "ou=users,dc=example,dc=com".
-                      Optional, when not specified it will be defaulted based on the
-                      host, for example if your active directory host is "activedirectory.example.com:636",
-                      it will be "dc=activedirectory,dc=example,dc=com".
+                      Optional, when not specified it will search the whole directory
+                      tree. Note that if your bind user only has permission to search
+                      a subtree, this must be specified. Search a subtree will also
+                      be faster.
                     type: string
                   filter:
                     description: Filter is the ActiveDirectory search filter which
diff --git a/generated/1.20/README.adoc b/generated/1.20/README.adoc
index 13051452..2eccb623 100644
--- a/generated/1.20/README.adoc
+++ b/generated/1.20/README.adoc
@@ -875,7 +875,7 @@ Status of an Active Directory identity provider.
 [cols="25a,75a", options="header"]
 |===
 | Field | Description
-| *`base`* __string__ | Base is the dn (distinguished name) that should be used as the search base when searching for users. E.g. "ou=users,dc=example,dc=com". Optional, when not specified it will be defaulted based on the host, for example if your active directory host is "activedirectory.example.com:636", it will be "dc=activedirectory,dc=example,dc=com".
+| *`base`* __string__ | Base is the dn (distinguished name) that should be used as the search base when searching for users. E.g. "ou=users,dc=example,dc=com". Optional, when not specified it will search the whole directory tree. Note that if your bind user only has permission to search a subtree, this must be specified. Search a subtree will also be faster.
 | *`filter`* __string__ | Filter is the ActiveDirectory search filter which should be applied when searching for users. The pattern "{}" must occur in the filter at least once and will be dynamically replaced by the username for which the search is being run. E.g. "mail={}" or "&(objectClass=person)(uid={})". For more information about ActiveDirectory filters, see https://ldap.com/ldap-filters. Note that the dn (distinguished name) is not an attribute of an entry, so "dn={}" cannot be used. Optional. When not specified, the default will act as if the Filter were specified as the value from Attributes.Username appended by "={}". When the Attributes.Username is set to "dn" then the Filter must be explicitly specified, since the default value of "dn={}" would not work.
 | *`attributes`* __xref:{anchor_prefix}-go-pinniped-dev-generated-1-20-apis-supervisor-idp-v1alpha1-activedirectoryidentityproviderusersearchattributes[$$ActiveDirectoryIdentityProviderUserSearchAttributes$$]__ | Attributes specifies how the user's information should be read from the ActiveDirectory entry which was found as the result of the user search.
 |===
diff --git a/generated/1.20/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go b/generated/1.20/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go
index 18726e7b..dc108466 100644
--- a/generated/1.20/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go
+++ b/generated/1.20/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go
@@ -72,8 +72,9 @@ type ActiveDirectoryIdentityProviderGroupSearchAttributes struct {
 type ActiveDirectoryIdentityProviderUserSearch struct {
 	// Base is the dn (distinguished name) that should be used as the search base when searching for users.
 	// E.g. "ou=users,dc=example,dc=com".
-	// Optional, when not specified it will be defaulted based on the host, for example if your active directory host is
-	// "activedirectory.example.com:636", it will be "dc=activedirectory,dc=example,dc=com".
+	// Optional, when not specified it will search the whole directory tree.
+	// Note that if your bind user only has permission to search a subtree, this must be specified.
+	// Search a subtree will also be faster.
 	// +optional
 	Base string `json:"base,omitempty"`
 
diff --git a/generated/1.20/crds/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml b/generated/1.20/crds/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml
index 03fbcd08..0f94c50a 100644
--- a/generated/1.20/crds/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml
+++ b/generated/1.20/crds/idp.supervisor.pinniped.dev_activedirectoryidentityproviders.yaml
@@ -155,9 +155,10 @@ spec:
                   base:
                     description: Base is the dn (distinguished name) that should be
                       used as the search base when searching for users. E.g. "ou=users,dc=example,dc=com".
-                      Optional, when not specified it will be defaulted based on the
-                      host, for example if your active directory host is "activedirectory.example.com:636",
-                      it will be "dc=activedirectory,dc=example,dc=com".
+                      Optional, when not specified it will search the whole directory
+                      tree. Note that if your bind user only has permission to search
+                      a subtree, this must be specified. Search a subtree will also
+                      be faster.
                     type: string
                   filter:
                     description: Filter is the ActiveDirectory search filter which
diff --git a/generated/latest/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go b/generated/latest/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go
index 18726e7b..dc108466 100644
--- a/generated/latest/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go
+++ b/generated/latest/apis/supervisor/idp/v1alpha1/types_activedirectoryidentityprovider.go
@@ -72,8 +72,9 @@ type ActiveDirectoryIdentityProviderGroupSearchAttributes struct {
 type ActiveDirectoryIdentityProviderUserSearch struct {
 	// Base is the dn (distinguished name) that should be used as the search base when searching for users.
 	// E.g. "ou=users,dc=example,dc=com".
-	// Optional, when not specified it will be defaulted based on the host, for example if your active directory host is
-	// "activedirectory.example.com:636", it will be "dc=activedirectory,dc=example,dc=com".
+	// Optional, when not specified it will search the whole directory tree.
+	// Note that if your bind user only has permission to search a subtree, this must be specified.
+	// Search a subtree will also be faster.
 	// +optional
 	Base string `json:"base,omitempty"`
 
diff --git a/internal/upstreamad/upstreamad.go b/internal/upstreamad/upstreamad.go
index 37fe3912..c64be5bb 100644
--- a/internal/upstreamad/upstreamad.go
+++ b/internal/upstreamad/upstreamad.go
@@ -417,19 +417,7 @@ func (p *Provider) userSearchRequest(username string) *ldap.SearchRequest {
 
 func (p *Provider) userSearchBase() string {
 	if len(p.c.UserSearch.Base) == 0 {
-		parsed, err := endpointaddr.Parse(p.c.Host, 636)
-		if err != nil {
-			return ""
-		}
-		dcParts := strings.Split(parsed.Host, ".")
-		base := ""
-		for i, dcPart := range dcParts {
-			base += "dc=" + dcPart
-			if i < len(dcParts)-1 {
-				base += ","
-			}
-		}
-		return base
+		return ""
 	}
 	return p.c.UserSearch.Base
 }
diff --git a/internal/upstreamad/upstreamad_test.go b/internal/upstreamad/upstreamad_test.go
index 1fe0fca8..9c0c2a0b 100644
--- a/internal/upstreamad/upstreamad_test.go
+++ b/internal/upstreamad/upstreamad_test.go
@@ -218,7 +218,7 @@ func TestEndUserAuthentication(t *testing.T) {
 				conn.EXPECT().Search(expectedUserSearch(func(r *ldap.SearchRequest) {
 					r.Filter = "(" + sAMAccountNameAttributeName + "=" + testUpstreamUsername + ")"
 					r.Attributes = []string{sAMAccountNameAttributeName, testUserSearchUIDAttribute}
-					r.BaseDN = "dc=activedirectory,dc=example,dc=com"
+					r.BaseDN = ""
 				})).Return(&ldap.SearchResult{
 					Entries: []*ldap.Entry{
 						{
diff --git a/pkg/oidcclient/login.go b/pkg/oidcclient/login.go
index ffd827e9..b036eb14 100644
--- a/pkg/oidcclient/login.go
+++ b/pkg/oidcclient/login.go
@@ -228,7 +228,8 @@ func WithRequestAudience(audience string) Option {
 // WithCLISendingCredentials causes the login flow to use CLI-based prompts for username and password and causes the
 // call to the Issuer's authorize endpoint to be made directly (no web browser) with the username and password on custom
 // HTTP headers. This is only intended to be used when the issuer is a Pinniped Supervisor and the upstream identity
-// provider type supports this style of authentication. Currently this is supported by LDAPIdentityProviders.
+// provider type supports this style of authentication. Currently this is supported by LDAPIdentityProviders and
+// ActiveDirectoryIdentityProviders.
 // This should never be used with non-Supervisor issuers because it will send the user's password to the authorization
 // endpoint as a custom header, which would be ignored but could potentially get logged somewhere by the issuer.
 func WithCLISendingCredentials() Option {
diff --git a/test/integration/supervisor_login_test.go b/test/integration/supervisor_login_test.go
index b747beaf..e1d1049f 100644
--- a/test/integration/supervisor_login_test.go
+++ b/test/integration/supervisor_login_test.go
@@ -230,6 +230,9 @@ func TestSupervisorLogin(t *testing.T) {
 			wantDownstreamIDTokenUsernameToMatch: regexp.QuoteMeta(env.SupervisorUpstreamLDAP.TestUserDN),
 			wantDownstreamIDTokenGroups:          env.SupervisorUpstreamLDAP.TestUserDirectGroupsCNs,
 		},
+		{
+			name: "activedirectory with all default options",
+		},
 	}
 	for _, test := range tests {
 		tt := test