diff --git a/README.md b/README.md
index 47ae458..1268002 100644
--- a/README.md
+++ b/README.md
@@ -44,6 +44,7 @@ There are also reasons not to choose this package. Because of all it does, this
     - [Overriding When Extending](#overriding-when-extending)
   - [Subschemas](#subschemas)
   - [Extracting Schemas](#extracting-schemas)
+  - [Raw Definition](#raw-definition)
 - [Schema Keys](#schema-keys)
 - [Schema Rules](#schema-rules)
   - [type](#type)
@@ -609,6 +610,23 @@ const addressSchema = schema.getObjectSchema('address');
 // });
 ```
 
+### Raw Definition
+
+Sometimes if you want to get the `rawDefinition` of some schema just pass in the options `{ keepRawDefinition: true}`(if not arg is passed the value will be null). Example:
+```javascript
+ const userSchema = new SimpleSchema({
+   name: String,
+   number: 'SimpleSchema.Integer',
+   email: String
+}, { keepRawDefintion: true });
+userSchema.rawDefinition;
+//{
+//   name: String,
+//   number: 'SimpleSchema.Integer',
+//   email: String
+//}
+``` 
+
 ## Schema Keys
 
 A basic schema key is just the name of the key (property) to expect in the objects that will be validated.
diff --git a/package/lib/SimpleSchema.js b/package/lib/SimpleSchema.js
index a36aace..fa3d312 100644
--- a/package/lib/SimpleSchema.js
+++ b/package/lib/SimpleSchema.js
@@ -76,12 +76,22 @@ class SimpleSchema {
     this._depsLabels = {};
     this.extend(schema);
 
+    // Clone raw definition and save if keepRawDefinition is active
+    this._rawDefinition = this._constructorOptions.keepRawDefinition ? schema : null;
+
     // Define default validation error messages
     this.messageBox = new MessageBox(clone(defaultMessages));
 
     this.version = SimpleSchema.version;
   }
 
+  /**
+  /* @returns {Object} The entire raw schema definition passed in the constructor
+  */
+  get rawDefinition() {
+    return this._rawDefinition;
+  }
+
   forEachAncestorSimpleSchema(key, func) {
     const genericKey = MongoObject.makeKeyGeneric(key);
 
diff --git a/package/lib/SimpleSchema.tests.js b/package/lib/SimpleSchema.tests.js
index ae6c14a..445de87 100644
--- a/package/lib/SimpleSchema.tests.js
+++ b/package/lib/SimpleSchema.tests.js
@@ -1144,6 +1144,22 @@ describe('SimpleSchema', function () {
     expect(foo instanceof SimpleSchema).toBe(true);
   });
 
+  it('issue #390 - Should get null rawDefinition if keepRawDefiniton is false', function () {
+    const foo = new SimpleSchema({
+      foo: String,
+    });
+    expect(foo instanceof SimpleSchema).toBe(true);
+    expect(foo.rawDefinition).toEqual(null);
+  });
+
+  it('issue #390 - Should get rawDefinition if keepRawDefiniton is true', function () {
+    const foo = new SimpleSchema({
+      foo: String,
+    }, { keepRawDefinition: true });
+    expect(foo instanceof SimpleSchema).toBe(true);
+    expect(foo.rawDefinition).toEqual({ foo: String });
+  });
+
   describe('SimpleSchema.Any', function () {
     const schema = new SimpleSchema({
       testAny: SimpleSchema.Any,