diff --git a/NSObject+Motis.h b/NSObject+Motis.h
index bc54497..3256234 100644
--- a/NSObject+Motis.h
+++ b/NSObject+Motis.h
@@ -87,7 +87,6 @@
 
 @end
 
-
 /*
  * MOTIS AUTOMATIC VALIDATION
  *
diff --git a/NSObject+Motis.m b/NSObject+Motis.m
index aabec5c..d9f6a86 100644
--- a/NSObject+Motis.m
+++ b/NSObject+Motis.m
@@ -70,6 +70,11 @@ - (id)initWithKeyPath:(NSString*)keyPath
 
 @end
 
+#pragma mark -
+// ------------------------------------------------------------------------------------------------------------------------------------------------------------------ //
+// ------------------------------------------------------------------------------------------------------------------------------------------------------------------ //
+// ------------------------------------------------------------------------------------------------------------------------------------------------------------------ //
+
 @interface NSObject (Motis_Private)
 
 /** ---------------------------------------------- **
@@ -114,12 +119,12 @@ - (NSString*)mts_typeAttributeForKey:(NSString*)key;
 - (BOOL)mts_isClassTypeTypeAttribute:(NSString*)typeAttribute;
 
 /**
- * Returns the class object for the given attribute type or nil if cannot be created.
+ * Retrieve the class name and the array of protocols that the property implements.
+ * @param className The returning class name.
+ * @param protocols The returning array of protocols.
  * @param typeAttribute The value returned by `-mts_typeAttributeForKey:`.
- * @return The related class object.
  */
-- (Class)mts_classForTypeAttribute:(NSString*)typeAttribute;
-
+- (void)mts_getClassName:(out NSString *__autoreleasing*)className protocols:(out NSArray *__autoreleasing*)protocols fromTypeAttribute:(NSString*)typeAttribute;
 
 /** ---------------------------------------------- **
  * @name Automatic Validation
@@ -567,15 +572,28 @@ - (BOOL)mts_isClassTypeTypeAttribute:(NSString*)typeAttribute
     return [typeAttribute hasPrefix:@"T@"] && ([typeAttribute length] > 1);
 }
 
-- (Class)mts_classForTypeAttribute:(NSString*)typeAttribute
+- (void)mts_getClassName:(out NSString *__autoreleasing*)className protocols:(out NSArray *__autoreleasing*)protocols fromTypeAttribute:(NSString*)typeAttribute
 {
     if ([self mts_isClassTypeTypeAttribute:typeAttribute])
     {
-        NSString *typeClassName = [typeAttribute substringWithRange:NSMakeRange(3, [typeAttribute length]-4)];
-        return NSClassFromString(typeClassName);
+        typeAttribute = [typeAttribute substringWithRange:NSMakeRange(3, typeAttribute.length-4)];
+        
+        NSString *protocolNames = nil;
+        
+        NSScanner *scanner = [NSScanner scannerWithString:typeAttribute];
+        [scanner scanUpToString:@"<" intoString:className];
+        [scanner scanUpToString:@">" intoString:&protocolNames];
+        
+        if (*className == nil)
+            *className = @"";
+        
+        if (protocolNames.length > 0)
+        {
+            protocolNames = [protocolNames substringFromIndex:1];
+            protocolNames = [protocolNames stringByReplacingOccurrencesOfString:@" " withString:@""];
+            *protocols = [protocolNames componentsSeparatedByString:@","];
+        }
     }
-    
-    return nil;
 }
 
 - (BOOL)mts_validateAutomaticallyValue:(inout __autoreleasing id *)ioValue forKey:(NSString*)key
@@ -593,15 +611,35 @@ - (BOOL)mts_validateAutomaticallyValue:(inout __autoreleasing id *)ioValue forKe
     
     if ([self mts_isClassTypeTypeAttribute:typeAttribute])
     {
-        if (strcmp(rawPropertyType, @encode(id)) == 0)
-            return YES;
+        NSString *className = nil;
+        NSArray *protocols = nil;
         
-        Class typeClass = [self mts_classForTypeAttribute:typeAttribute];
+        [self mts_getClassName:&className protocols:&protocols fromTypeAttribute:typeAttribute];
         
-        if (typeClass != nil)
+        if (className.length == 0)
         {
-            MJLog(@"%@ --> %@", key, NSStringFromClass(typeClass));
-            return [self mts_validateAutomaticallyValue:ioValue toClass:typeClass forKey:key];
+            // It's an "id".
+            
+            // Actually, we should make a compare like this:
+            // if (strcmp(rawPropertyType, @encode(id)) == 0)
+            //    return YES;
+            //
+            // However, becuase of the "if" statements, we know that our typeAttribute begins with a "@" and
+            // if "className.length" == 0 means that the "rawPropertyType" to be compared is exactly an @encode(id).
+            //
+            // Therefore, we return directly YES.
+            
+            return YES;
+        }
+        else
+        {
+            Class typeClass = NSClassFromString(className);
+            
+            if (typeClass)
+            {
+                MJLog(@"%@ --> %@", key, NSStringFromClass(typeClass));
+                return [self mts_validateAutomaticallyValue:ioValue toClass:typeClass forKey:key];
+            }
         }
         
         return NO;
diff --git a/SampleProject/Motis Tests/MJTestObject.h b/SampleProject/Motis Tests/MJTestObject.h
index 4f65cf8..79d38ed 100644
--- a/SampleProject/Motis Tests/MJTestObject.h	
+++ b/SampleProject/Motis Tests/MJTestObject.h	
@@ -22,6 +22,9 @@
 @property (nonatomic, strong) NSNumber *numberField;
 @property (nonatomic, strong) NSURL *urlField;
 
+@property (nonatomic, strong) id idField;
+@property (nonatomic, strong) id <NSObject> idProtocolField;
+
 
 // This property is not included in the mapping
 @property (nonatomic, strong) NSString *privateStringField;
diff --git a/SampleProject/Motis Tests/MJTestObject.m b/SampleProject/Motis Tests/MJTestObject.m
index 2d2f312..3830ff0 100644
--- a/SampleProject/Motis Tests/MJTestObject.m	
+++ b/SampleProject/Motis Tests/MJTestObject.m	
@@ -26,6 +26,9 @@ + (NSDictionary*)mts_mapping
              @"number": mts_key(numberField),
              @"url": mts_key(urlField),
              
+             @"id": mts_key(idField),
+             @"id_protocol": mts_key(idProtocolField),
+             
              @"string1.string2.string3" : mts_key(stringField),
              @"url1.url2.url3" : mts_key(urlField),
              };
diff --git a/SampleProject/Motis Tests/Motis_Tests.m b/SampleProject/Motis Tests/Motis_Tests.m
index 3b8f739..5246a95 100644
--- a/SampleProject/Motis Tests/Motis_Tests.m	
+++ b/SampleProject/Motis Tests/Motis_Tests.m	
@@ -175,6 +175,30 @@ - (void)testNumberToString
     }
 }
 
+#pragma mark to id
+
+- (void)testNumberToId
+{
+    for (NSNumber *number in [self mts_arrayWithNumbers])
+    {
+        _object.idField = nil;
+        [_object mts_setValue:number forKey:@"id"];
+        if (![_object.idField isEqualToNumber:number])
+            XCTFail(@"Failed to map number value %@", number.description);
+    }
+}
+
+- (void)testNumberToIdProtocol
+{
+    for (NSNumber *number in [self mts_arrayWithNumbers])
+    {
+        _object.idField = nil;
+        [_object mts_setValue:number forKey:@"id_protocol"];
+        if (![(NSNumber*)_object.idProtocolField isEqualToNumber:number])
+            XCTFail(@"Failed to map number value %@", number.description);
+    }
+}
+
 #pragma mark - FROM STRING
 
 // ------------------------------------------------------------------------------------------------------------------------ //
@@ -274,6 +298,26 @@ - (void)testStringToUrl
         XCTFail(@"Failed to map string value %@", string);
 }
 
+#pragma mark to id
+
+- (void)testStringToId
+{
+    NSString *string = @"Hello World";
+    [_object mts_setValue:string forKey:@"id"];
+    
+    if (![_object.idField isEqualToString:string])
+        XCTFail(@"Failed to map string value %@", string);
+}
+
+- (void)testStringToIdProtocol
+{
+    NSString *string = @"Hello World";
+    [_object mts_setValue:string forKey:@"id_protocol"];
+    
+    if (![(NSString*)_object.idProtocolField isEqualToString:string])
+        XCTFail(@"Failed to map string value %@", string);
+}
+
 #pragma mark - FROM DICTIONARY
 
 // ------------------------------------------------------------------------------------------------------------------------ //
diff --git a/SampleProject/Motis/MJAppDelegate.m b/SampleProject/Motis/MJAppDelegate.m
index e3aae66..cdb8a0c 100644
--- a/SampleProject/Motis/MJAppDelegate.m
+++ b/SampleProject/Motis/MJAppDelegate.m
@@ -25,7 +25,7 @@ @implementation MJAppDelegate
 
 - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
 {
-    //[self performTest]; // <--- UNCOMMENT FOR TESTING
+    [self performTest]; // <--- UNCOMMENT FOR TESTING
     
     UIWindow *window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
     window.rootViewController = [[UIViewController alloc] init];
diff --git a/SampleProject/Motis/MJUser.h b/SampleProject/Motis/MJUser.h
index 5d61aa2..50a9912 100644
--- a/SampleProject/Motis/MJUser.h
+++ b/SampleProject/Motis/MJUser.h
@@ -16,6 +16,8 @@
 
 #import <Foundation/Foundation.h>
 
+#import "Motis.h"
+
 @interface MJUser : NSObject
 
 @property (nonatomic, assign) NSNumber *userId;
diff --git a/SampleProject/Motis/MJVideo.h b/SampleProject/Motis/MJVideo.h
index 5468e81..b39dd13 100644
--- a/SampleProject/Motis/MJVideo.h
+++ b/SampleProject/Motis/MJVideo.h
@@ -16,7 +16,7 @@
 
 #import <Foundation/Foundation.h>
 
-@class MJUser;
+#import "MJUser.h"
 
 /** ********************************************************* **
  *  @name JSON Entity Attributes
@@ -62,8 +62,9 @@
 
 /**
  * Title of the video.
+ * @discussion Just for testing porpuses we set the NSString type as an id <NSObject>.
  **/
-@property (nonatomic, strong) NSString *title;
+@property (nonatomic, strong) id <NSObject> title;
 
 /**
  * Description of the video.