diff --git a/AFNetworking/AFHTTPRequestOperation.h b/AFNetworking/AFHTTPRequestOperation.h
index 350b64a..ea6bfd0 100644
--- a/AFNetworking/AFHTTPRequestOperation.h
+++ b/AFNetworking/AFHTTPRequestOperation.h
@@ -31,6 +31,8 @@
     NSIndexSet *_acceptableStatusCodes;
     NSSet *_acceptableContentTypes;
     NSError *_HTTPError;
+    dispatch_queue_t _successCallbackQueue;
+    dispatch_queue_t _failureCallbackQueue;
 }
 
 ///----------------------------------------------
@@ -71,6 +73,17 @@
  */
 @property (readonly) BOOL hasAcceptableContentType;
 
+/** 
+ The callback dispatch queue on success. If this is NULL (default), the main queue is used.
+ */
+@property (nonatomic) dispatch_queue_t successCallbackQueue;
+
+/** 
+ The callback dispatch queue on failure. If this is NULL (default), the main queue is used.
+ */
+@property (nonatomic) dispatch_queue_t failureCallbackQueue;
+
+
 /**
  A Boolean value determining whether or not the class can process the specified request. For example, `AFJSONRequestOperation` may check to make sure the content type was `application/json` or the URL path extension was `.json`.
  
@@ -94,3 +107,18 @@
                               failure:(void (^)(AFHTTPRequestOperation *operation, NSError *error))failure;
 
 @end
+
+
+@interface AFHTTPRequestOperation (AFInternal)
+
+/**
+ Executes the successBlock on the corresponding successCallbackQueue.
+ */
+- (void)dispatchSuccessBlock:(void (^)(AFHTTPRequestOperation *operation, id responseObject))successBlock responseObject:(id)responseObject;
+
+/**
+ Executes the failureBlock on the corresponding failureCallbackQueue.
+ */
+- (void)dispatchFailureBlock:(void (^)(AFHTTPRequestOperation *operation, NSError *error))failureBlock;
+
+@end
\ No newline at end of file
diff --git a/AFNetworking/AFHTTPRequestOperation.m b/AFNetworking/AFHTTPRequestOperation.m
index 38802c1..591c56e 100644
--- a/AFNetworking/AFHTTPRequestOperation.m
+++ b/AFNetworking/AFHTTPRequestOperation.m
@@ -30,6 +30,9 @@
 @synthesize acceptableStatusCodes = _acceptableStatusCodes;
 @synthesize acceptableContentTypes = _acceptableContentTypes;
 @synthesize HTTPError = _HTTPError;
+@synthesize successCallbackQueue = _successCallbackQueue;
+@synthesize failureCallbackQueue = _failureCallbackQueue;
+
 
 - (id)initWithRequest:(NSURLRequest *)request {
     self = [super initWithRequest:request];
@@ -46,6 +49,8 @@
     [_acceptableStatusCodes release];
     [_acceptableContentTypes release];
     [_HTTPError release];
+    if (_successCallbackQueue) { dispatch_release(_successCallbackQueue), _successCallbackQueue=NULL;}
+    if (_failureCallbackQueue) { dispatch_release(_failureCallbackQueue), _failureCallbackQueue=NULL;}
     [super dealloc];
 }
 
@@ -85,6 +90,34 @@
     return !self.acceptableContentTypes || [self.acceptableContentTypes containsObject:[self.response MIMEType]];
 }
 
+- (void)setSuccessCallbackQueue:(dispatch_queue_t)successCallbackQueue {
+    if (successCallbackQueue != _successCallbackQueue) {
+        
+        if (_successCallbackQueue) {
+            dispatch_release(_successCallbackQueue);
+        }
+     
+        if (successCallbackQueue) {
+            dispatch_retain(successCallbackQueue);
+            _successCallbackQueue = successCallbackQueue;
+        }
+    }    
+}
+
+- (void)setFailureCallbackQueue:(dispatch_queue_t)failureCallbackQueue {
+    if (failureCallbackQueue != _failureCallbackQueue) {
+        
+        if (_failureCallbackQueue) {
+            dispatch_release(_failureCallbackQueue);
+        }
+        
+        if (failureCallbackQueue) {
+            dispatch_retain(failureCallbackQueue);
+            _failureCallbackQueue = failureCallbackQueue;
+        }
+    }    
+}
+
 - (void)setCompletionBlockWithSuccess:(void (^)(AFHTTPRequestOperation *operation, id responseObject))success
                               failure:(void (^)(AFHTTPRequestOperation *operation, NSError *error))failure
 {
@@ -94,17 +127,9 @@
         }
         
         if (self.error) {
-            if (failure) {
-                dispatch_async(dispatch_get_main_queue(), ^(void) {
-                    failure(self, self.error);
-                });
-            }
+            [self dispatchFailureBlock:failure];
         } else {
-            if (success) {
-                dispatch_async(dispatch_get_main_queue(), ^{
-                    success(self, self.responseData);
-                });
-            }
+            [self dispatchSuccessBlock:success responseObject:self.responseString];
         }
     };
 }
@@ -113,6 +138,24 @@
 
 + (BOOL)canProcessRequest:(NSURLRequest *)request {
     return YES;
-}     
+}
+
+#pragma mark - AFInternal
+
+- (void)dispatchSuccessBlock:(void (^)(AFHTTPRequestOperation *operation, id responseObject))successBlock responseObject:(id)responseObject {
+    if (successBlock) {
+        dispatch_async(self.successCallbackQueue ? self.successCallbackQueue : dispatch_get_main_queue(), ^{
+            successBlock(self, responseObject);
+        });
+    }
+}
+
+- (void)dispatchFailureBlock:(void (^)(AFHTTPRequestOperation *operation, NSError *error))failureBlock {
+    if (failureBlock) {
+        dispatch_async(self.failureCallbackQueue ? self.failureCallbackQueue : dispatch_get_main_queue(), ^{
+            failureBlock(self, self.error);
+        });
+    }
+}
 
 @end
diff --git a/AFNetworking/AFImageRequestOperation.m b/AFNetworking/AFImageRequestOperation.m
index f28d497..f732a3c 100644
--- a/AFNetworking/AFImageRequestOperation.m
+++ b/AFNetworking/AFImageRequestOperation.m
@@ -230,17 +230,9 @@ static dispatch_queue_t image_request_operation_processing_queue() {
         
         dispatch_async(image_request_operation_processing_queue(), ^(void) {
             if (self.error) {
-                if (failure) {
-                    dispatch_async(dispatch_get_main_queue(), ^(void) {
-                        failure(self, self.error);
-                    });
-                }
-            } else {                
-                if (success) {
-                    dispatch_async(dispatch_get_main_queue(), ^(void) {
-                        success(self, self.responseImage);
-                    });
-                }
+                [self dispatchFailureBlock:failure];
+            } else {            
+                [self dispatchSuccessBlock:success responseObject:self.responseImage];
             }
         });        
     };  
diff --git a/AFNetworking/AFJSONRequestOperation.m b/AFNetworking/AFJSONRequestOperation.m
index 5c651de..6d39413 100644
--- a/AFNetworking/AFJSONRequestOperation.m
+++ b/AFNetworking/AFJSONRequestOperation.m
@@ -124,26 +124,16 @@ static dispatch_queue_t json_request_operation_processing_queue() {
         }
         
         if (self.error) {
-            if (failure) {
-                dispatch_async(dispatch_get_main_queue(), ^(void) {
-                    failure(self, self.error);
-                });
-            }
+            [self dispatchFailureBlock:failure];
         } else {
             dispatch_async(json_request_operation_processing_queue(), ^(void) {
                 id JSON = self.responseJSON;
                 
-                dispatch_async(dispatch_get_main_queue(), ^(void) {
-                    if (self.JSONError) {
-                        if (failure) {
-                            failure(self, self.JSONError);
-                        }
-                    } else {
-                        if (success) {
-                            success(self, JSON);
-                        }
-                    }
-                }); 
+                if (self.JSONError) {
+                    [self dispatchFailureBlock:failure];
+                } else {
+                    [self dispatchSuccessBlock:success responseObject:JSON];
+                }
             });
         }
     };    
diff --git a/AFNetworking/AFPropertyListRequestOperation.m b/AFNetworking/AFPropertyListRequestOperation.m
index bb7a41b..d294cd2 100644
--- a/AFNetworking/AFPropertyListRequestOperation.m
+++ b/AFNetworking/AFPropertyListRequestOperation.m
@@ -124,26 +124,16 @@ static dispatch_queue_t property_list_request_operation_processing_queue() {
         }
         
         if (self.error) {
-            if (failure) {
-                dispatch_async(dispatch_get_main_queue(), ^(void) {
-                    failure(self, self.error);
-                });
-            }
+            [self dispatchFailureBlock:failure];
         } else {
             dispatch_async(property_list_request_operation_processing_queue(), ^(void) {
                 id propertyList = self.responsePropertyList;
-
-                dispatch_async(dispatch_get_main_queue(), ^(void) {
-                    if (self.propertyListError) {
-                        if (failure) {
-                            failure(self, self.propertyListError);
-                        }
-                    } else {
-                        if (success) {
-                            success(self, propertyList);
-                        }
-                    }
-                }); 
+                
+                if (self.propertyListError) {
+                    [self dispatchFailureBlock:failure];
+                }else {
+                    [self dispatchSuccessBlock:success responseObject:propertyList];
+                }
             });
         }
     };    
diff --git a/AFNetworking/AFXMLRequestOperation.m b/AFNetworking/AFXMLRequestOperation.m
index b6b3a2b..7b50fd6 100644
--- a/AFNetworking/AFXMLRequestOperation.m
+++ b/AFNetworking/AFXMLRequestOperation.m
@@ -187,15 +187,9 @@ static dispatch_queue_t xml_request_operation_processing_queue() {
         }
         
         if (self.error) {
-            if (failure) {
-                dispatch_async(dispatch_get_main_queue(), ^(void) {
-                    failure(self, self.error);
-                });
-            }
+            [self dispatchFailureBlock:failure];
         } else {
-            if (success) {
-                success(self, self.responseXMLParser);
-            }
+            [self dispatchSuccessBlock:success responseObject:self.responseXMLParser];
         }
     };    
 }