diff --git a/src/contexts/context.validator.ts b/src/contexts/context.validator.ts
index da3210b..a4db467 100644
--- a/src/contexts/context.validator.ts
+++ b/src/contexts/context.validator.ts
@@ -1,7 +1,7 @@
 import * as Joi from 'joi';
 
 export const createContextModel = Joi.object().keys({
-  scope: Joi.string().required(),
+  scope: Joi.string().required().valid('public', 'protected', 'private'),
   alias: Joi.string(),
   properties_map:  Joi.object().required().keys({
     center: Joi.string(),
@@ -10,7 +10,7 @@ export const createContextModel = Joi.object().keys({
 });
 
 export const updateContextModel = Joi.object().keys({
-    scope: Joi.string(),
+    scope: Joi.string().valid('public', 'protected', 'private'),
     alias: Joi.string(),
     properties_map:  Joi.object().required().keys({
       center: Joi.string(),