diff --git a/pkg.go b/pkg.go
index 932684e..4eebce1 100644
--- a/pkg.go
+++ b/pkg.go
@@ -54,9 +54,10 @@ const VERSION = "v0.1.0"
 
 type HttpHandler func(http.ResponseWriter, *http.Request)
 
-type ErrorHandler func(err error, w http.ResponseWriter)
+type ErrorHandler func(err error, code string, w http.ResponseWriter)
 type ServiceError struct {
 	OK    bool
+	Code  string
 	Error string
 }
 
@@ -115,10 +116,11 @@ func (service *Service) defaultAuthorizationHandler(sess *session.T, r *http.Req
 	service.logger.Debug("webservice", "op", "authorization", "session", sess.UUID, "request", r.URL.String(), "authorized", resp)
 	return
 } // }}}
-func (service *Service) defaultErrorHandler(err error, w http.ResponseWriter) { // {{{
+func (service *Service) defaultErrorHandler(err error, code string, w http.ResponseWriter) { // {{{
 	service.logger.Error("webservice", "error", err)
 	errMsg := ServiceError{}
 	errMsg.OK = false
+	errMsg.Code = code
 	errMsg.Error = err.Error()
 	errJSON, _ := json.Marshal(errMsg)
 	w.Write(errJSON)
@@ -158,7 +160,7 @@ func (service *Service) SetDatabase(sqlProv database.SqlProvider) { // {{{
 } // }}}
 func (service *Service) Register(path string, requireSession, requireAuthentication bool, handler ServiceHandler) { // {{{
 	http.HandleFunc(path, func(w http.ResponseWriter, r *http.Request) {
-		var session *session.T
+		var sess *session.T
 		var found bool
 		var authorized bool
 		var err error
@@ -170,35 +172,35 @@ func (service *Service) Register(path string, requireSession, requireAuthenticat
 		if requireSession {
 			headerSessionUUID, err := sessionUUID(r)
 			if err != nil {
-				service.errorHandler(fmt.Errorf("Header X-Session-ID missing"), w)
+				service.errorHandler(fmt.Errorf("Header X-Session-ID missing"), "001-0000", w)
 				return
 			}
 
-			session, found = service.retrieveSession(headerSessionUUID)
+			sess, found = service.retrieveSession(headerSessionUUID)
 			if !found {
-				service.errorHandler(fmt.Errorf("Session '%s' not found", headerSessionUUID), w)
+				service.errorHandler(fmt.Errorf("Session '%s' not found", headerSessionUUID), "001-0001", w)
 				return
 			}
 		}
 
 		if requireAuthentication {
-			if !session.Authenticated {
-				service.errorHandler(fmt.Errorf("Session '%s' not authenticated", session.UUID), w)
+			if !sess.Authenticated {
+				service.errorHandler(fmt.Errorf("Session '%s' not authenticated", sess.UUID), "001-0002", w)
 				return
 			}
 
-			authorized, err = service.authorizationHandler(session, r)
+			authorized, err = service.authorizationHandler(sess, r)
 			if err != nil {
-				service.errorHandler(err, w)
+				service.errorHandler(err, "001-F001", w)
 				return
 			}
 			if !authorized {
-				service.errorHandler(fmt.Errorf("Session '%s' not authorized for %s", session.UUID, r.URL.String()), w)
+				service.errorHandler(fmt.Errorf("Session '%s' not authorized for %s", sess.UUID, r.URL.String()), "001-0003", w)
 				return
 			}
 		}
 
-		handler(w, r, session)
+		handler(w, r, sess)
 	})
 } // }}}
 func (service *Service) InitDatabaseConnection() (err error) { // {{{
diff --git a/session.go b/session.go
index c556df3..d612f57 100644
--- a/session.go
+++ b/session.go
@@ -28,31 +28,31 @@ type AuthenticationResponse struct {
 type AuthenticationHandler func(AuthenticationRequest, bool) (AuthenticationResponse, error)
 type AuthorizationHandler func(*session.T, *http.Request) (bool, error)
 
-func (service *Service) sessionNew(w http.ResponseWriter, r *http.Request, sess *session.T) { // {{{
-	var session session.T
+func (service *Service) sessionNew(w http.ResponseWriter, r *http.Request, foo *session.T) { // {{{
+	var sess session.T
 	var found bool
 	var err error
 
 	for {
-		session.UUID = uuid.NewString()
+		sess.UUID = uuid.NewString()
 		if service.Db == nil {
-			if _, found = service.sessions[session.UUID]; found {
+			if _, found = service.sessions[sess.UUID]; found {
 				continue
 			}
 
-			session.Authenticated = false
-			session.Created = time.Now()
-			service.sessions[session.UUID] = &session
+			sess.Authenticated = false
+			sess.Created = time.Now()
+			service.sessions[sess.UUID] = &sess
 			break
 
 		} else {
-			if _, found = service.retrieveSession(session.UUID); found {
+			if _, found = service.retrieveSession(sess.UUID); found {
 				continue
 			}
 
-			err = service.Db.NewSession(session.UUID)
+			err = service.Db.NewSession(sess.UUID)
 			if err != nil {
-				service.errorHandler(err, w)
+				service.errorHandler(err, "001-A001", w)
 				return
 			}
 			break
@@ -60,15 +60,15 @@ func (service *Service) sessionNew(w http.ResponseWriter, r *http.Request, sess
 
 	}
 
-	service.logger.Info("session", "op", "new", "uuid", session.UUID)
+	service.logger.Info("session", "op", "new", "uuid", sess.UUID)
 
 	respJSON, _ := json.Marshal(
 		struct {
 			OK   bool
-			UUID string
+			Session session.T
 		}{
 			true,
-			session.UUID,
+			sess,
 		},
 	)
 
@@ -84,7 +84,7 @@ func (service *Service) sessionAuthenticate(w http.ResponseWriter, r *http.Reque
 	var authRequest AuthenticationRequest
 	err = json.Unmarshal(reqBody, &authRequest)
 	if err != nil {
-		service.errorHandler(err, w)
+		service.errorHandler(err, "001-0004", w)
 		return
 	}
 
@@ -93,14 +93,14 @@ func (service *Service) sessionAuthenticate(w http.ResponseWriter, r *http.Reque
 	if service.Db != nil {
 		authenticated, userID, err = service.Db.Authenticate(authRequest.Username, authRequest.Password)
 		if err != nil {
-			service.errorHandler(err, w)
+			service.errorHandler(err, "001-A002", w)
 			return
 		}
 
 		if authenticated && userID > 0 {
 			err = service.Db.SetSessionUser(sess.UUID, userID)
 			if err != nil {
-				service.errorHandler(err, w)
+				service.errorHandler(err, "001-A003", w)
 				return
 			}
 		}
@@ -111,7 +111,7 @@ func (service *Service) sessionAuthenticate(w http.ResponseWriter, r *http.Reque
 	// and given a chance to override it.
 	authResponse, err = service.authenticationHandler(authRequest, authenticated)
 	if err != nil {
-		service.errorHandler(err, w)
+		service.errorHandler(err, "001-F002", w)
 		return
 	}
 	authResponse.UserID = userID