diff --git a/README.md b/README.md
index 3776dd3e3..7b35b1bfe 100644
--- a/README.md
+++ b/README.md
@@ -332,6 +332,19 @@ You should use `isType` for all Schema type checks.
 Sets the `strict` option to `true`. Strict schemas skip coercion and transformation attempts,
 validating the value "as is".
 
+#### `mixed.strip(stripField: boolean = true): Schema`
+
+Marks a schema to be removed from an output object. Only works as a nested schema.
+
+```js
+let schema = object({
+  useThis: number(),
+  notThis: string().strip()
+})
+
+schema.cast({ notThis: 'foo', useThis: 4 }) // { useThis: 4 }
+```
+
 #### `mixed.withMutation(builder: (current: Schema) => void): void`
 
 First the legally required Rich Hickey quote:
@@ -817,6 +830,19 @@ yup.object().shape({
 })
 ```
 
+You can also pass a shape to the object constructor as a convenience.
+
+```js
+object().shape({
+  num: number()
+})
+//or
+object({
+  num: number()
+})
+```
+
+
 #### `object.shape(fields: object, noSortEdges: ?Array<[string, string]>): Schema`
 
 Define the keys of the object and the schemas for said keys.
diff --git a/lib/date.js b/lib/date.js
index 53a8528d3..9e632d894 100644
--- a/lib/date.js
+++ b/lib/date.js
@@ -4,6 +4,7 @@ var MixedSchema = require('./mixed');
 var isoParse = require('./util/isodate');
 var locale = require('./locale.js').date;
 var isAbsent = require('./util/isAbsent');
+var Ref = require('./util/reference');
 
 var _require = require('./util/_');
 
@@ -37,9 +38,12 @@ inherits(DateSchema, MixedSchema, {
     return isDate(v) && !isNaN(v.getTime());
   },
   min: function min(_min, msg) {
-    var limit = this.cast(_min);
+    var limit = _min;
 
-    if (!this._typeCheck(limit)) throw new TypeError('`min` must be a Date or a value that can be `cast()` to a Date');
+    if (!Ref.isRef(limit)) {
+      limit = this.cast(_min);
+      if (!this._typeCheck(limit)) throw new TypeError('`min` must be a Date or a value that can be `cast()` to a Date');
+    }
 
     return this.test({
       name: 'min',
@@ -52,9 +56,12 @@ inherits(DateSchema, MixedSchema, {
     });
   },
   max: function max(_max, msg) {
-    var limit = this.cast(_max);
+    var limit = _max;
 
-    if (!this._typeCheck(limit)) throw new TypeError('`max` must be a Date or a value that can be `cast()` to a Date');
+    if (!Ref.isRef(limit)) {
+      limit = this.cast(_max);
+      if (!this._typeCheck(limit)) throw new TypeError('`max` must be a Date or a value that can be `cast()` to a Date');
+    }
 
     return this.test({
       name: 'max',
diff --git a/src/locale.js b/src/locale.js
index 8e1c2bee8..44a04f699 100644
--- a/src/locale.js
+++ b/src/locale.js
@@ -18,7 +18,7 @@ module.exports = {
     url:       '${path} must be a valid URL',
     trim:      '${path} must be a trimmed string',
     lowercase: '${path} must be a lowercase string',
-    uppercase: '${path} must be a uppercase string'
+    uppercase: '${path} must be a upper case string'
   },
 
   number: {
diff --git a/src/mixed.js b/src/mixed.js
index 8bb2a3077..f88739f83 100644
--- a/src/mixed.js
+++ b/src/mixed.js
@@ -382,6 +382,12 @@ SchemaType.prototype = {
     return next
   },
 
+  strip(strip = true) {
+    let next = this.clone()
+    next._strip = strip
+    return next
+  },
+
   _option(key, overrides){
     return _.has(overrides, key)
       ? overrides[key] : this._options[key]
diff --git a/src/object.js b/src/object.js
index 368d10bb6..4706fd677 100644
--- a/src/object.js
+++ b/src/object.js
@@ -49,6 +49,10 @@ function ObjectSchema(spec) {
     }
   })
 
+  this.fields = Object.create(null)
+  this._nodes = []
+  this._excludedEdges = []
+
   this.withMutation(() => {
     this.transform(function coerce(value) {
       if (typeof value === 'string') {
@@ -61,14 +65,10 @@ function ObjectSchema(spec) {
         return value
       return null
     })
-  })
-
-  this.fields = Object.create(null)
-  this._nodes = []
-  this._excludedEdges = []
 
-  if ( spec )
-    return this.shape(spec);
+    if (spec)
+      this.shape(spec);
+  })
 }
 
 inherits(ObjectSchema, MixedSchema, {
@@ -106,17 +106,13 @@ inherits(ObjectSchema, MixedSchema, {
             obj[prop] = refValue
         }
         else if (exists && field) {
-          // ugly optimization avoiding a clone. clears default for recursive
-          // cast and resets it below;
-          let hasDflt = has(schema, '_default')
-            , dflt = schema._default;
-
-          let fieldSchema = childSchema(field, schema.default(undefined))
-
-          obj[prop] = fieldSchema.cast(value[prop], innerOptions)
+          tempClearDefault(schema, () => {
+            let fieldSchema = childSchema(field, schema.default(undefined))
 
-          if (hasDflt) schema.default(dflt)
-          else delete schema._default
+            if (fieldSchema._strip !== true) {
+              obj[prop] = fieldSchema.cast(value[prop], innerOptions)
+            }
+          })
         }
         else if (exists && !strip)
           obj[prop] = value[prop]
@@ -253,6 +249,18 @@ function unknown(ctx, value) {
     .filter(key => known.indexOf(key) === -1)
 }
 
+// ugly optimization avoiding a clone. clears default for recursive
+// cast and resets it below;
+function tempClearDefault(schema, fn) {
+  let hasDflt = has(schema, '_default')
+    , dflt = schema._default;
+
+  fn(schema)
+
+  if (hasDflt) schema.default(dflt)
+  else delete schema._default
+}
+
 function sortFields(fields, excludes = []){
   var edges = [], nodes = []
 
diff --git a/test/object.js b/test/object.js
index f3813e3a7..1f81e5a19 100644
--- a/test/object.js
+++ b/test/object.js
@@ -229,6 +229,18 @@ describe('Object types', function(){
     ])
   })
 
+  it('should strip specific fields', function(){
+    var inst = object().shape({
+          prop: mixed().strip(false),
+          other: mixed().strip()
+        })
+
+    inst.cast({ other: 'boo', prop: 'bar'})
+      .should.eql({
+        prop: 'bar'
+      })
+  })
+
   it('should handle custom validation', function(){
     var inst = object().shape({
       prop: mixed(),