diff --git a/src/compiler/utilities.ts b/src/compiler/utilities.ts
index 4df840c3241..6d89fb6cc83 100644
--- a/src/compiler/utilities.ts
+++ b/src/compiler/utilities.ts
@@ -780,6 +780,8 @@ module ts {
                         return node === (<TemplateSpan>parent).expression;
                     case SyntaxKind.ComputedPropertyName:
                         return node === (<ComputedPropertyName>parent).expression;
+                    case SyntaxKind.Decorator:
+                        return true;
                     default:
                         if (isExpression(parent)) {
                             return true;
diff --git a/tests/baselines/reference/decoratorOnClass1.types b/tests/baselines/reference/decoratorOnClass1.types
index 19e066586da..91c9feb4e35 100644
--- a/tests/baselines/reference/decoratorOnClass1.types
+++ b/tests/baselines/reference/decoratorOnClass1.types
@@ -7,7 +7,7 @@ declare function dec<T>(target: T): T;
 >T : T
 
 @dec
->dec : unknown
+>dec : <T>(target: T) => T
 
 class C {
 >C : C
diff --git a/tests/baselines/reference/decoratorOnClass2.types b/tests/baselines/reference/decoratorOnClass2.types
index 43102ee9122..48565b74b43 100644
--- a/tests/baselines/reference/decoratorOnClass2.types
+++ b/tests/baselines/reference/decoratorOnClass2.types
@@ -7,7 +7,7 @@ declare function dec<T>(target: T): T;
 >T : T
 
 @dec
->dec : unknown
+>dec : <T>(target: T) => T
 
 export class C {
 >C : C
diff --git a/tests/baselines/reference/decoratorOnClassAccessor1.types b/tests/baselines/reference/decoratorOnClassAccessor1.types
index fd592d7d294..602faf1fd22 100644
--- a/tests/baselines/reference/decoratorOnClassAccessor1.types
+++ b/tests/baselines/reference/decoratorOnClassAccessor1.types
@@ -14,6 +14,6 @@ class C {
 >C : C
 
     @dec get accessor() { return 1; }
->dec : unknown
+>dec : <T>(target: any, propertyKey: string, descriptor: TypedPropertyDescriptor<T>) => TypedPropertyDescriptor<T>
 >accessor : number
 }
diff --git a/tests/baselines/reference/decoratorOnClassAccessor2.types b/tests/baselines/reference/decoratorOnClassAccessor2.types
index 32bb503d889..e43733db132 100644
--- a/tests/baselines/reference/decoratorOnClassAccessor2.types
+++ b/tests/baselines/reference/decoratorOnClassAccessor2.types
@@ -14,6 +14,6 @@ class C {
 >C : C
 
     @dec public get accessor() { return 1; }
->dec : unknown
+>dec : <T>(target: any, propertyKey: string, descriptor: TypedPropertyDescriptor<T>) => TypedPropertyDescriptor<T>
 >accessor : number
 }
diff --git a/tests/baselines/reference/decoratorOnClassAccessor4.types b/tests/baselines/reference/decoratorOnClassAccessor4.types
index 40dd43d7e62..59399c5ea31 100644
--- a/tests/baselines/reference/decoratorOnClassAccessor4.types
+++ b/tests/baselines/reference/decoratorOnClassAccessor4.types
@@ -14,7 +14,7 @@ class C {
 >C : C
 
     @dec set accessor(value: number) { }
->dec : unknown
+>dec : <T>(target: any, propertyKey: string, descriptor: TypedPropertyDescriptor<T>) => TypedPropertyDescriptor<T>
 >accessor : number
 >value : number
 }
diff --git a/tests/baselines/reference/decoratorOnClassAccessor5.types b/tests/baselines/reference/decoratorOnClassAccessor5.types
index 4b167fe8df1..8fe5ee55368 100644
--- a/tests/baselines/reference/decoratorOnClassAccessor5.types
+++ b/tests/baselines/reference/decoratorOnClassAccessor5.types
@@ -14,7 +14,7 @@ class C {
 >C : C
 
     @dec public set accessor(value: number) { }
->dec : unknown
+>dec : <T>(target: any, propertyKey: string, descriptor: TypedPropertyDescriptor<T>) => TypedPropertyDescriptor<T>
 >accessor : number
 >value : number
 }
diff --git a/tests/baselines/reference/decoratorOnClassConstructorParameter1.types b/tests/baselines/reference/decoratorOnClassConstructorParameter1.types
index d5ce51269bc..a325945d8a2 100644
--- a/tests/baselines/reference/decoratorOnClassConstructorParameter1.types
+++ b/tests/baselines/reference/decoratorOnClassConstructorParameter1.types
@@ -10,6 +10,6 @@ class C {
 >C : C
 
     constructor(@dec p: number) {}
->dec : unknown
+>dec : (target: Function, propertyKey: string | symbol, parameterIndex: number) => void
 >p : number
 }
diff --git a/tests/baselines/reference/decoratorOnClassMethod1.types b/tests/baselines/reference/decoratorOnClassMethod1.types
index 760f758bbff..fc7f27c5dfb 100644
--- a/tests/baselines/reference/decoratorOnClassMethod1.types
+++ b/tests/baselines/reference/decoratorOnClassMethod1.types
@@ -14,6 +14,6 @@ class C {
 >C : C
 
     @dec method() {}
->dec : unknown
+>dec : <T>(target: any, propertyKey: string, descriptor: TypedPropertyDescriptor<T>) => TypedPropertyDescriptor<T>
 >method : () => void
 }
diff --git a/tests/baselines/reference/decoratorOnClassMethod11.js b/tests/baselines/reference/decoratorOnClassMethod11.js
index 71d4298f02c..f8276de2fe3 100644
--- a/tests/baselines/reference/decoratorOnClassMethod11.js
+++ b/tests/baselines/reference/decoratorOnClassMethod11.js
@@ -1,11 +1,11 @@
 //// [decoratorOnClassMethod11.ts]
-module M {
-    class C {
-        decorator(target: Object, key: string): void { }
-
-        @this.decorator
-        method() { }
-    }
+module M {
+    class C {
+        decorator(target: Object, key: string): void { }
+
+        @this.decorator
+        method() { }
+    }
 }
 
 //// [decoratorOnClassMethod11.js]
diff --git a/tests/baselines/reference/decoratorOnClassMethod13.types b/tests/baselines/reference/decoratorOnClassMethod13.types
index 8c34805792f..1390f5750e6 100644
--- a/tests/baselines/reference/decoratorOnClassMethod13.types
+++ b/tests/baselines/reference/decoratorOnClassMethod13.types
@@ -14,8 +14,8 @@ class C {
 >C : C
 
     @dec ["1"]() { }
->dec : unknown
+>dec : () => <T>(target: any, propertyKey: string, descriptor: TypedPropertyDescriptor<T>) => TypedPropertyDescriptor<T>
 
     @dec ["b"]() { }
->dec : unknown
+>dec : () => <T>(target: any, propertyKey: string, descriptor: TypedPropertyDescriptor<T>) => TypedPropertyDescriptor<T>
 }
diff --git a/tests/baselines/reference/decoratorOnClassMethod2.types b/tests/baselines/reference/decoratorOnClassMethod2.types
index 98539648cd0..b83605c9c3c 100644
--- a/tests/baselines/reference/decoratorOnClassMethod2.types
+++ b/tests/baselines/reference/decoratorOnClassMethod2.types
@@ -14,6 +14,6 @@ class C {
 >C : C
 
     @dec public method() {}
->dec : unknown
+>dec : <T>(target: any, propertyKey: string, descriptor: TypedPropertyDescriptor<T>) => TypedPropertyDescriptor<T>
 >method : () => void
 }
diff --git a/tests/baselines/reference/decoratorOnClassMethod4.types b/tests/baselines/reference/decoratorOnClassMethod4.types
index 6d55e01e97a..5b48b267e1d 100644
--- a/tests/baselines/reference/decoratorOnClassMethod4.types
+++ b/tests/baselines/reference/decoratorOnClassMethod4.types
@@ -14,5 +14,5 @@ class C {
 >C : C
 
     @dec ["method"]() {}
->dec : unknown
+>dec : <T>(target: any, propertyKey: string, descriptor: TypedPropertyDescriptor<T>) => TypedPropertyDescriptor<T>
 }
diff --git a/tests/baselines/reference/decoratorOnClassMethod6.types b/tests/baselines/reference/decoratorOnClassMethod6.types
index 4e6629cd60a..8b167b5fb0f 100644
--- a/tests/baselines/reference/decoratorOnClassMethod6.types
+++ b/tests/baselines/reference/decoratorOnClassMethod6.types
@@ -14,5 +14,5 @@ class C {
 >C : C
 
     @dec ["method"]() {}
->dec : unknown
+>dec : () => <T>(target: any, propertyKey: string, descriptor: TypedPropertyDescriptor<T>) => TypedPropertyDescriptor<T>
 }
diff --git a/tests/baselines/reference/decoratorOnClassMethod7.types b/tests/baselines/reference/decoratorOnClassMethod7.types
index 7e426cb773c..038d3ca7df5 100644
--- a/tests/baselines/reference/decoratorOnClassMethod7.types
+++ b/tests/baselines/reference/decoratorOnClassMethod7.types
@@ -14,5 +14,5 @@ class C {
 >C : C
 
     @dec public ["method"]() {}
->dec : unknown
+>dec : <T>(target: any, propertyKey: string, descriptor: TypedPropertyDescriptor<T>) => TypedPropertyDescriptor<T>
 }
diff --git a/tests/baselines/reference/decoratorOnClassMethod8.types b/tests/baselines/reference/decoratorOnClassMethod8.types
index f932ab8696f..20890b09846 100644
--- a/tests/baselines/reference/decoratorOnClassMethod8.types
+++ b/tests/baselines/reference/decoratorOnClassMethod8.types
@@ -10,6 +10,6 @@ class C {
 >C : C
 
     @dec method() {}
->dec : unknown
+>dec : <T>(target: T) => T
 >method : () => void
 }
diff --git a/tests/baselines/reference/decoratorOnClassMethodParameter1.types b/tests/baselines/reference/decoratorOnClassMethodParameter1.types
index cf7bfd352bf..0b75471471f 100644
--- a/tests/baselines/reference/decoratorOnClassMethodParameter1.types
+++ b/tests/baselines/reference/decoratorOnClassMethodParameter1.types
@@ -11,6 +11,6 @@ class C {
 
     method(@dec p: number) {}
 >method : (p: number) => void
->dec : unknown
+>dec : (target: Function, propertyKey: string | symbol, parameterIndex: number) => void
 >p : number
 }
diff --git a/tests/baselines/reference/decoratorOnClassProperty1.types b/tests/baselines/reference/decoratorOnClassProperty1.types
index 651085c7ac4..e974397e532 100644
--- a/tests/baselines/reference/decoratorOnClassProperty1.types
+++ b/tests/baselines/reference/decoratorOnClassProperty1.types
@@ -8,6 +8,6 @@ class C {
 >C : C
 
     @dec prop;
->dec : unknown
+>dec : (target: any, propertyKey: string) => void
 >prop : any
 }
diff --git a/tests/baselines/reference/decoratorOnClassProperty11.types b/tests/baselines/reference/decoratorOnClassProperty11.types
index 5377e53c31c..5caa467d3ba 100644
--- a/tests/baselines/reference/decoratorOnClassProperty11.types
+++ b/tests/baselines/reference/decoratorOnClassProperty11.types
@@ -9,6 +9,6 @@ class C {
 >C : C
 
     @dec prop;
->dec : unknown
+>dec : () => <T>(target: any, propertyKey: string) => void
 >prop : any
 }
diff --git a/tests/baselines/reference/decoratorOnClassProperty2.types b/tests/baselines/reference/decoratorOnClassProperty2.types
index 2d5c9fe07d7..78d35004f8f 100644
--- a/tests/baselines/reference/decoratorOnClassProperty2.types
+++ b/tests/baselines/reference/decoratorOnClassProperty2.types
@@ -8,6 +8,6 @@ class C {
 >C : C
 
     @dec public prop;
->dec : unknown
+>dec : (target: any, propertyKey: string) => void
 >prop : any
 }
diff --git a/tests/baselines/reference/decoratorOnClassProperty6.types b/tests/baselines/reference/decoratorOnClassProperty6.types
index 2c8c41abf78..59d03678330 100644
--- a/tests/baselines/reference/decoratorOnClassProperty6.types
+++ b/tests/baselines/reference/decoratorOnClassProperty6.types
@@ -8,6 +8,6 @@ class C {
 >C : C
 
     @dec prop;
->dec : unknown
+>dec : (target: Function) => void
 >prop : any
 }
diff --git a/tests/baselines/reference/sourceMapValidationDecorators.types b/tests/baselines/reference/sourceMapValidationDecorators.types
index 8be7f237391..05b512fa439 100644
--- a/tests/baselines/reference/sourceMapValidationDecorators.types
+++ b/tests/baselines/reference/sourceMapValidationDecorators.types
@@ -43,7 +43,7 @@ declare function ParameterDecorator2(x: number): (target: Function, key: string
 >paramIndex : number
 
 @ClassDecorator1
->ClassDecorator1 : unknown
+>ClassDecorator1 : (target: Function) => void
 
 @ClassDecorator2(10)
 >ClassDecorator2(10) : (target: Function) => void
@@ -54,7 +54,7 @@ class Greeter {
 
     constructor(
       @ParameterDecorator1 
->ParameterDecorator1 : unknown
+>ParameterDecorator1 : (target: Function, key: string | symbol, paramIndex: number) => void
 
       @ParameterDecorator2(20) 
 >ParameterDecorator2(20) : (target: Function, key: string | symbol, paramIndex: number) => void
@@ -64,7 +64,7 @@ class Greeter {
 >greeting : string
       
       @ParameterDecorator1 
->ParameterDecorator1 : unknown
+>ParameterDecorator1 : (target: Function, key: string | symbol, paramIndex: number) => void
 
       @ParameterDecorator2(30) 
 >ParameterDecorator2(30) : (target: Function, key: string | symbol, paramIndex: number) => void
@@ -75,7 +75,7 @@ class Greeter {
     }
     
     @PropertyDecorator1
->PropertyDecorator1 : unknown
+>PropertyDecorator1 : (target: Object, key: string | symbol, descriptor?: PropertyDescriptor) => void
 
     @PropertyDecorator2(40)
 >PropertyDecorator2(40) : (target: Object, key: string | symbol, descriptor?: PropertyDescriptor) => void
@@ -93,7 +93,7 @@ class Greeter {
     }
 
     @PropertyDecorator1
->PropertyDecorator1 : unknown
+>PropertyDecorator1 : (target: Object, key: string | symbol, descriptor?: PropertyDescriptor) => void
 
     @PropertyDecorator2(50)
 >PropertyDecorator2(50) : (target: Object, key: string | symbol, descriptor?: PropertyDescriptor) => void
@@ -103,7 +103,7 @@ class Greeter {
 >x : string
 
     @PropertyDecorator1
->PropertyDecorator1 : unknown
+>PropertyDecorator1 : (target: Object, key: string | symbol, descriptor?: PropertyDescriptor) => void
 
     @PropertyDecorator2(60)
 >PropertyDecorator2(60) : (target: Object, key: string | symbol, descriptor?: PropertyDescriptor) => void
@@ -116,7 +116,7 @@ class Greeter {
 >fn : (x: number) => string
 
       @ParameterDecorator1 
->ParameterDecorator1 : unknown
+>ParameterDecorator1 : (target: Function, key: string | symbol, paramIndex: number) => void
 
       @ParameterDecorator2(70) 
 >ParameterDecorator2(70) : (target: Function, key: string | symbol, paramIndex: number) => void
@@ -132,7 +132,7 @@ class Greeter {
     }
 
     @PropertyDecorator1
->PropertyDecorator1 : unknown
+>PropertyDecorator1 : (target: Object, key: string | symbol, descriptor?: PropertyDescriptor) => void
 
     @PropertyDecorator2(80)
 >PropertyDecorator2(80) : (target: Object, key: string | symbol, descriptor?: PropertyDescriptor) => void
@@ -151,7 +151,7 @@ class Greeter {
 >greetings : string
 
       @ParameterDecorator1 
->ParameterDecorator1 : unknown
+>ParameterDecorator1 : (target: Function, key: string | symbol, paramIndex: number) => void
 
       @ParameterDecorator2(90) 
 >ParameterDecorator2(90) : (target: Function, key: string | symbol, paramIndex: number) => void
diff --git a/tests/cases/fourslash/findAllRefsOnDecorators.ts b/tests/cases/fourslash/findAllRefsOnDecorators.ts
new file mode 100644
index 00000000000..3225bc108ce
--- /dev/null
+++ b/tests/cases/fourslash/findAllRefsOnDecorators.ts
@@ -0,0 +1,19 @@
+/// <reference path="fourslash.ts" />
+
+// @Filename: a.ts
+////function decorator(target) {
+////    return target;
+////}
+////decorator();
+
+// @Filename: b.ts
+////@deco/*1*/rator @decorator("again")
+////class C {
+////    @decorator
+////    method() {}
+////}
+
+goTo.file("b.ts");
+goTo.marker("1");
+
+verify.referencesCountIs(5);
\ No newline at end of file
diff --git a/tests/cases/fourslash/getOccurrencesOfDecorators.ts b/tests/cases/fourslash/getOccurrencesOfDecorators.ts
new file mode 100644
index 00000000000..207e6877d99
--- /dev/null
+++ b/tests/cases/fourslash/getOccurrencesOfDecorators.ts
@@ -0,0 +1,14 @@
+/// <reference path='fourslash.ts' />
+
+// @Filename: b.ts
+////@/*1*/decorator
+////class C {
+////    @decorator
+////    method() {}
+////}
+////function decorator(target) {
+////    return target;
+////}
+
+goTo.marker("1");
+verify.occurrencesAtPositionCount(3);
diff --git a/tests/cases/fourslash/goToDefinitionDecorator.ts b/tests/cases/fourslash/goToDefinitionDecorator.ts
new file mode 100644
index 00000000000..b0899a9576c
--- /dev/null
+++ b/tests/cases/fourslash/goToDefinitionDecorator.ts
@@ -0,0 +1,26 @@
+/// <reference path='fourslash.ts' />
+
+// @Filename: b.ts
+////@/*decoratorUse*/decorator
+////class C {
+////    @decora/*decoratorFactoryUse*/torFactory(a, "22", true)
+////    method() {}
+////}
+
+
+// @Filename: a.ts
+/////*decoratorDefinition*/function decorator(target) {
+////    return target;
+////}
+/////*decoratorFactoryDefinition*/function decoratorFactory(...args) {
+////    return target => target;
+////}
+
+
+goTo.marker('decoratorUse');
+goTo.definition();
+verify.caretAtMarker('decoratorDefinition');
+
+goTo.marker('decoratorFactoryUse');
+goTo.definition();
+verify.caretAtMarker('decoratorFactoryDefinition');
diff --git a/tests/cases/fourslash/quickInfoForDecorators.ts b/tests/cases/fourslash/quickInfoForDecorators.ts
new file mode 100644
index 00000000000..14390f3c8ae
--- /dev/null
+++ b/tests/cases/fourslash/quickInfoForDecorators.ts
@@ -0,0 +1,11 @@
+/// <reference path='fourslash.ts' />
+
+////@/*1*/decorator
+////class C {
+
+////}
+/////** decorator documentation*/
+////var decorator = t=> t;
+
+goTo.marker("1");
+verify.quickInfoIs("var decorator: (t: any) => any", "decorator documentation");
\ No newline at end of file