diff --git a/README.md b/README.md
index 4d3c62c..a19a842 100644
--- a/README.md
+++ b/README.md
@@ -98,6 +98,15 @@ of the user role's claim `https://github.com/i-core/werther/claims/roles`.
 ```
 
 To customize the roles claim's name you should set a value of the environment variable `WERTHER_LDAP_ROLE_CLAIM`.
+Also you should map the custom name of the roles' claim to a roles's scope using the environment variable
+`WERTHER_IDENTP_CLAIM_SCOPES` (the name must be [URL encoded][uri-spec-encoding]):
+
+```bash
+env WERTHER_LDAP_ROLE_CLAIM=https://my-company.com/claims/roles                                                                                     \
+    WERTHER_IDENTP_CLAIM_SCOPES=name:profile,family_name:profile,given_name:profile,email:email,https%3A%2F%2Fmy-company.com%2Fclaims%2Froles:roles \
+    werther
+```
+
 For more details about claims naming see [OpenID Connect Core 1.0][oidc-spec-additional-claims].
 
 **NB** There are cases when we need to create several roles with the same name in LDAP.
@@ -353,3 +362,5 @@ The code in this project is licensed under [MIT license][license].
 [oidc-spec-session]: https://openid.net/specs/openid-connect-session-1_0.html
 [oidc-spec-front-channel-logout]: https://openid.net/specs/openid-connect-frontchannel-1_0.html
 [oidc-spec-back-channel-logout]: https://openid.net/specs/openid-connect-backchannel-1_0.html
+
+[uri-spec-encoding]: https://tools.ietf.org/html/rfc3986#section-2
diff --git a/cmd/werther/main.go b/cmd/werther/main.go
index c4fb7d0..f3685a2 100644
--- a/cmd/werther/main.go
+++ b/cmd/werther/main.go
@@ -11,6 +11,7 @@ import (
 	"flag"
 	"fmt"
 	"net/http"
+	"net/url"
 	"os"
 
 	"github.com/i-core/rlog"
@@ -58,6 +59,10 @@ func main() {
 		fmt.Fprintf(os.Stderr, "Invalid configuration: %s\n", err)
 		os.Exit(1)
 	}
+	if _, ok := cnf.Identp.ClaimScopes[url.QueryEscape(cnf.LDAP.RoleClaim)]; !ok {
+		fmt.Fprintf(os.Stderr, "Roles claim %q has no mapping to an OpenID Connect scope\n", cnf.LDAP.RoleClaim)
+		os.Exit(1)
+	}
 
 	logFunc := zap.NewProduction
 	if cnf.DevMode {
diff --git a/internal/identp/identp.go b/internal/identp/identp.go
index 32bdffe..ebffe05 100644
--- a/internal/identp/identp.go
+++ b/internal/identp/identp.go
@@ -29,7 +29,7 @@ const loginTmplName = "login.tmpl"
 type Config struct {
 	HydraURL    string            `envconfig:"hydra_url" required:"true" desc:"an admin URL of ORY Hydra Server"`
 	SessionTTL  time.Duration     `envconfig:"session_ttl" default:"24h" desc:"a user session's TTL"`
-	ClaimScopes map[string]string `envconfig:"claim_scopes" default:"name:profile,family_name:profile,given_name:profile,email:email,http%3A%2F%2Ffithub.com%2Fi-core.ru%2Fwerther%2Fclaims%2Froles:roles" desc:"a mapping of OpenID Connect claims to scopes (all claims are URL encoded)"`
+	ClaimScopes map[string]string `envconfig:"claim_scopes" default:"name:profile,family_name:profile,given_name:profile,email:email,https%3A%2F%2Fgithub.com%2Fi-core%2Fwerther%2Fclaims%2Froles:roles" desc:"a mapping of OpenID Connect claims to scopes (all claims are URL encoded)"`
 }
 
 // UserManager is an interface that is used for authentication and providing user's claims.