diff --git a/pkg/oidc/introspection.go b/pkg/oidc/introspection.go
new file mode 100644
index 0000000..7fa13de
--- /dev/null
+++ b/pkg/oidc/introspection.go
@@ -0,0 +1,256 @@
+package oidc
+
+import (
+	"encoding/json"
+	"fmt"
+	"time"
+
+	"golang.org/x/text/language"
+
+	"github.com/caos/oidc/pkg/utils"
+)
+
+type IntrospectionRequest struct {
+	Token string `schema:"token"`
+}
+
+type IntrospectionResponse interface {
+	UserInfoSetter
+	SetActive(bool)
+	IsActive() bool
+}
+
+func NewIntrospectionResponse() IntrospectionResponse {
+	return &introspectionResponse{}
+}
+
+type introspectionResponse struct {
+	Active  bool   `json:"active"`
+	Subject string `json:"sub,omitempty"`
+	userInfoProfile
+	userInfoEmail
+	userInfoPhone
+	Address UserInfoAddress `json:"address,omitempty"`
+
+	claims map[string]interface{}
+}
+
+func (u *introspectionResponse) IsActive() bool {
+	return u.Active
+}
+func (u *introspectionResponse) GetSubject() string {
+	return u.Subject
+}
+
+func (u *introspectionResponse) GetName() string {
+	return u.Name
+}
+
+func (u *introspectionResponse) GetGivenName() string {
+	return u.GivenName
+}
+
+func (u *introspectionResponse) GetFamilyName() string {
+	return u.FamilyName
+}
+
+func (u *introspectionResponse) GetMiddleName() string {
+	return u.MiddleName
+}
+
+func (u *introspectionResponse) GetNickname() string {
+	return u.Nickname
+}
+
+func (u *introspectionResponse) GetProfile() string {
+	return u.Profile
+}
+
+func (u *introspectionResponse) GetPicture() string {
+	return u.Picture
+}
+
+func (u *introspectionResponse) GetWebsite() string {
+	return u.Website
+}
+
+func (u *introspectionResponse) GetGender() Gender {
+	return u.Gender
+}
+
+func (u *introspectionResponse) GetBirthdate() string {
+	return u.Birthdate
+}
+
+func (u *introspectionResponse) GetZoneinfo() string {
+	return u.Zoneinfo
+}
+
+func (u *introspectionResponse) GetLocale() language.Tag {
+	return u.Locale
+}
+
+func (u *introspectionResponse) GetPreferredUsername() string {
+	return u.PreferredUsername
+}
+
+func (u *introspectionResponse) GetEmail() string {
+	return u.Email
+}
+
+func (u *introspectionResponse) IsEmailVerified() bool {
+	return u.EmailVerified
+}
+
+func (u *introspectionResponse) GetPhoneNumber() string {
+	return u.PhoneNumber
+}
+
+func (u *introspectionResponse) IsPhoneNumberVerified() bool {
+	return u.PhoneNumberVerified
+}
+
+func (u *introspectionResponse) GetAddress() UserInfoAddress {
+	return u.Address
+}
+
+func (u *introspectionResponse) GetClaim(key string) interface{} {
+	return u.claims[key]
+}
+
+func (u *introspectionResponse) SetActive(active bool) {
+	u.Active = active
+}
+
+func (u *introspectionResponse) SetSubject(sub string) {
+	u.Subject = sub
+}
+
+func (u *introspectionResponse) SetName(name string) {
+	u.Name = name
+}
+
+func (u *introspectionResponse) SetGivenName(name string) {
+	u.GivenName = name
+}
+
+func (u *introspectionResponse) SetFamilyName(name string) {
+	u.FamilyName = name
+}
+
+func (u *introspectionResponse) SetMiddleName(name string) {
+	u.MiddleName = name
+}
+
+func (u *introspectionResponse) SetNickname(name string) {
+	u.Nickname = name
+}
+
+func (u *introspectionResponse) SetUpdatedAt(date time.Time) {
+	u.UpdatedAt = Time(date)
+}
+
+func (u *introspectionResponse) SetProfile(profile string) {
+	u.Profile = profile
+}
+
+func (u *introspectionResponse) SetPicture(picture string) {
+	u.Picture = picture
+}
+
+func (u *introspectionResponse) SetWebsite(website string) {
+	u.Website = website
+}
+
+func (u *introspectionResponse) SetGender(gender Gender) {
+	u.Gender = gender
+}
+
+func (u *introspectionResponse) SetBirthdate(birthdate string) {
+	u.Birthdate = birthdate
+}
+
+func (u *introspectionResponse) SetZoneinfo(zoneInfo string) {
+	u.Zoneinfo = zoneInfo
+}
+
+func (u *introspectionResponse) SetLocale(locale language.Tag) {
+	u.Locale = locale
+}
+
+func (u *introspectionResponse) SetPreferredUsername(name string) {
+	u.PreferredUsername = name
+}
+
+func (u *introspectionResponse) SetEmail(email string, verified bool) {
+	u.Email = email
+	u.EmailVerified = verified
+}
+
+func (u *introspectionResponse) SetPhone(phone string, verified bool) {
+	u.PhoneNumber = phone
+	u.PhoneNumberVerified = verified
+}
+
+func (u *introspectionResponse) SetAddress(address UserInfoAddress) {
+	u.Address = address
+}
+
+func (u *introspectionResponse) AppendClaims(key string, value interface{}) {
+	if u.claims == nil {
+		u.claims = make(map[string]interface{})
+	}
+	u.claims[key] = value
+}
+
+func (i *introspectionResponse) MarshalJSON() ([]byte, error) {
+	type Alias introspectionResponse
+	a := &struct {
+		*Alias
+		Locale            interface{} `json:"locale,omitempty"`
+		UpdatedAt         int64       `json:"updated_at,omitempty"`
+		PreferredUsername string      `json:"username,omitempty"`
+	}{
+		Alias: (*Alias)(i),
+	}
+	if !i.Locale.IsRoot() {
+		a.Locale = i.Locale
+	}
+	if !time.Time(i.UpdatedAt).IsZero() {
+		a.UpdatedAt = time.Time(i.UpdatedAt).Unix()
+	}
+	a.PreferredUsername = i.PreferredUsername
+	i.PreferredUsername = ""
+
+	b, err := json.Marshal(a)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(i.claims) == 0 {
+		return b, nil
+	}
+
+	claims, err := json.Marshal(i.claims)
+	if err != nil {
+		return nil, fmt.Errorf("jws: invalid map of custom claims %v", i.claims)
+	}
+	return utils.ConcatenateJSON(b, claims)
+}
+
+func (i *introspectionResponse) UnmarshalJSON(data []byte) error {
+	type Alias introspectionResponse
+	a := &struct {
+		*Alias
+		UpdatedAt int64 `json:"update_at,omitempty"`
+	}{
+		Alias: (*Alias)(i),
+	}
+	if err := json.Unmarshal(data, &a); err != nil {
+		return err
+	}
+
+	i.UpdatedAt = Time(time.Unix(a.UpdatedAt, 0).UTC())
+
+	return nil
+}
diff --git a/pkg/op/config.go b/pkg/op/config.go
index a2b831e..f4fbb97 100644
--- a/pkg/op/config.go
+++ b/pkg/op/config.go
@@ -13,6 +13,7 @@ type Configuration interface {
 	Issuer() string
 	AuthorizationEndpoint() Endpoint
 	TokenEndpoint() Endpoint
+	IntrospectionEndpoint() Endpoint
 	UserinfoEndpoint() Endpoint
 	EndSessionEndpoint() Endpoint
 	KeysEndpoint() Endpoint
diff --git a/pkg/op/discovery.go b/pkg/op/discovery.go
index 4bc1272..3bec79b 100644
--- a/pkg/op/discovery.go
+++ b/pkg/op/discovery.go
@@ -22,9 +22,9 @@ func CreateDiscoveryConfig(c Configuration, s Signer) *oidc.DiscoveryConfigurati
 		Issuer:                c.Issuer(),
 		AuthorizationEndpoint: c.AuthorizationEndpoint().Absolute(c.Issuer()),
 		TokenEndpoint:         c.TokenEndpoint().Absolute(c.Issuer()),
-		// IntrospectionEndpoint: c.Intro().Absolute(c.Issuer()),
-		UserinfoEndpoint:   c.UserinfoEndpoint().Absolute(c.Issuer()),
-		EndSessionEndpoint: c.EndSessionEndpoint().Absolute(c.Issuer()),
+		IntrospectionEndpoint: c.IntrospectionEndpoint().Absolute(c.Issuer()),
+		UserinfoEndpoint:      c.UserinfoEndpoint().Absolute(c.Issuer()),
+		EndSessionEndpoint:    c.EndSessionEndpoint().Absolute(c.Issuer()),
 		// CheckSessionIframe: c.TokenEndpoint().Absolute(c.Issuer())(c.CheckSessionIframe),
 		JwksURI:                           c.KeysEndpoint().Absolute(c.Issuer()),
 		ScopesSupported:                   Scopes(c),
diff --git a/pkg/op/op.go b/pkg/op/op.go
index d16848e..76d5fcc 100644
--- a/pkg/op/op.go
+++ b/pkg/op/op.go
@@ -21,7 +21,7 @@ const (
 	readinessEndpoint            = "/ready"
 	defaultAuthorizationEndpoint = "authorize"
 	defaulTokenEndpoint          = "oauth/token"
-	defaultIntrospectEndpoint    = "introspect"
+	defaultIntrospectEndpoint    = "oauth/introspect"
 	defaultUserinfoEndpoint      = "userinfo"
 	defaultEndSessionEndpoint    = "end_session"
 	defaultKeysEndpoint          = "keys"
@@ -78,6 +78,7 @@ func CreateRouter(o OpenIDProvider, interceptors ...HttpInterceptor) *mux.Router
 	router.Handle(o.AuthorizationEndpoint().Relative(), intercept(authorizeHandler(o)))
 	router.NewRoute().Path(o.AuthorizationEndpoint().Relative()+"/callback").Queries("id", "{id}").Handler(intercept(authorizeCallbackHandler(o)))
 	router.Handle(o.TokenEndpoint().Relative(), intercept(tokenHandler(o)))
+	router.HandleFunc(o.IntrospectionEndpoint().Relative(), introspectionHandler(o))
 	router.HandleFunc(o.UserinfoEndpoint().Relative(), userinfoHandler(o))
 	router.Handle(o.EndSessionEndpoint().Relative(), intercept(endSessionHandler(o)))
 	router.HandleFunc(o.KeysEndpoint().Relative(), keysHandler(o))
@@ -166,6 +167,10 @@ func (o *openidProvider) TokenEndpoint() Endpoint {
 	return o.endpoints.Token
 }
 
+func (o *openidProvider) IntrospectionEndpoint() Endpoint {
+	return o.endpoints.Introspection
+}
+
 func (o *openidProvider) UserinfoEndpoint() Endpoint {
 	return o.endpoints.Userinfo
 }
@@ -332,6 +337,16 @@ func WithCustomTokenEndpoint(endpoint Endpoint) Option {
 	}
 }
 
+func WithCustomIntrospectionEndpoint(endpoint Endpoint) Option {
+	return func(o *openidProvider) error {
+		if err := endpoint.Validate(); err != nil {
+			return err
+		}
+		o.endpoints.Introspection = endpoint
+		return nil
+	}
+}
+
 func WithCustomUserinfoEndpoint(endpoint Endpoint) Option {
 	return func(o *openidProvider) error {
 		if err := endpoint.Validate(); err != nil {
diff --git a/pkg/op/storage.go b/pkg/op/storage.go
index eba5003..0a0cec2 100644
--- a/pkg/op/storage.go
+++ b/pkg/op/storage.go
@@ -28,10 +28,15 @@ type AuthStorage interface {
 type OPStorage interface {
 	GetClientByClientID(ctx context.Context, clientID string) (Client, error)
 	AuthorizeClientIDSecret(ctx context.Context, clientID, clientSecret string) error
-	GetUserinfoFromScopes(ctx context.Context, userID, clientID string, scopes []string) (oidc.UserInfo, error)
-	GetUserinfoFromToken(ctx context.Context, tokenID, subject, origin string) (oidc.UserInfo, error)
+	SetUserinfoFromScopes(ctx context.Context, userinfo oidc.UserInfoSetter, userID, clientID string, scopes []string) error
+	SetUserinfoFromToken(ctx context.Context, userinfo oidc.UserInfoSetter, tokenID, subject, origin string) error
 	GetPrivateClaimsFromScopes(ctx context.Context, userID, clientID string, scopes []string) (map[string]interface{}, error)
 	GetKeyByIDAndUserID(ctx context.Context, keyID, userID string) (*jose.JSONWebKey, error)
+
+	//deprecated: use GetUserinfoFromScopes instead
+	GetUserinfoFromScopes(ctx context.Context, userID, clientID string, scopes []string) (oidc.UserInfo, error)
+	//deprecated: use SetUserinfoFromToken instead
+	GetUserinfoFromToken(ctx context.Context, tokenID, subject, origin string) (oidc.UserInfo, error)
 }
 
 type Storage interface {
diff --git a/pkg/op/token_intospection.go b/pkg/op/token_intospection.go
new file mode 100644
index 0000000..e6a5d4a
--- /dev/null
+++ b/pkg/op/token_intospection.go
@@ -0,0 +1,58 @@
+package op
+
+import (
+	"errors"
+	"net/http"
+
+	"github.com/caos/oidc/pkg/oidc"
+	"github.com/caos/oidc/pkg/utils"
+)
+
+type Introspector interface {
+	Decoder() utils.Decoder
+	Crypto() Crypto
+	Storage() Storage
+	AccessTokenVerifier() AccessTokenVerifier
+}
+
+func introspectionHandler(introspector Introspector) func(http.ResponseWriter, *http.Request) {
+	return func(w http.ResponseWriter, r *http.Request) {
+		Introspect(w, r, introspector)
+	}
+}
+
+func Introspect(w http.ResponseWriter, r *http.Request, introspector Introspector) {
+	//validate authorization
+
+	response := oidc.NewIntrospectionResponse()
+	token, err := ParseTokenInrospectionRequest(r, introspector.Decoder())
+	if err != nil {
+		utils.MarshalJSON(w, response)
+		return
+	}
+	tokenID, subject, ok := getTokenIDAndSubject(r.Context(), introspector, token)
+	if !ok {
+		utils.MarshalJSON(w, response)
+		return
+	}
+	err = introspector.Storage().SetUserinfoFromToken(r.Context(), response, tokenID, subject, r.Header.Get("origin"))
+	if err != nil {
+		utils.MarshalJSON(w, response)
+		return
+	}
+	response.SetActive(true)
+	utils.MarshalJSON(w, response)
+}
+
+func ParseTokenInrospectionRequest(r *http.Request, decoder utils.Decoder) (string, error) {
+	err := r.ParseForm()
+	if err != nil {
+		return "", errors.New("unable to parse request")
+	}
+	req := new(oidc.IntrospectionRequest)
+	err = decoder.Decode(req, r.Form)
+	if err != nil {
+		return "", errors.New("unable to parse request")
+	}
+	return req.Token, nil
+}