diff --git a/CHANGELOG.md b/CHANGELOG.md
index 767a31cd5ad679..d32d9047fab67e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,9 +6,10 @@
 - [RaisedButton] Fix:className now set to root element(#3122)
 - [LeftNav] Fix:className and `style` now set to root element(#3322)
 - [Colors] Removed default export in favor of singular exports (#2825) <br>
-**Note** This can be temoporary worked around by changing <br>
+**Note** This can be temporarily worked around by changing <br>
 `import Colors from 'material-ui/lib/styles/colors';` <br> to <br>
 `import * as Colors from 'material-ui/lib/styles/colors';`.
+- [DatePicker] Standardize for ISO8601. (#3417)
 
 ## 0.14.4
 ###### _Feb 02, 2016_
diff --git a/ROADMAP.md b/ROADMAP.md
index f7809eb2606c9a..9215f6ff4ada81 100644
--- a/ROADMAP.md
+++ b/ROADMAP.md
@@ -9,7 +9,7 @@ The roadmap is a living document, and it is likely that priorities will change,
 - [x] Remove deprecated usage of JSON to generate children across the components.
 - [x] [[#3108](https://github.com/callemall/material-ui/pull/3108)] Remove deprecated components, methods & props.
 - [ ] [[#2957](https://github.com/callemall/material-ui/issues/2957)] Standardize callback signatures.
-- [ ] [[#2980](https://github.com/callemall/material-ui/issues/2980)] [[#1839](https://github.com/callemall/material-ui/issues/1839)] Standardise Datepicker for ISO8601.
+- [x] [[#2980](https://github.com/callemall/material-ui/issues/2980)] [[#1839](https://github.com/callemall/material-ui/issues/1839)] Standardise Datepicker for ISO8601.
 
 #### Deprecations
 
diff --git a/docs/src/app/components/pages/components/DatePicker/ExampleInternational.jsx b/docs/src/app/components/pages/components/DatePicker/ExampleInternational.jsx
index c1e08f7127170c..39be010a3511a6 100644
--- a/docs/src/app/components/pages/components/DatePicker/ExampleInternational.jsx
+++ b/docs/src/app/components/pages/components/DatePicker/ExampleInternational.jsx
@@ -4,26 +4,42 @@ import areIntlLocalesSupported from 'intl-locales-supported';
 
 let DateTimeFormat;
 
-// Use the native Intl if available
-if (areIntlLocalesSupported('fr')) {
+/**
+ * Use the native Intl.DateTimeFormat if available, or a polyfill if not.
+ */
+if (areIntlLocalesSupported(['fr', 'en-US'])) {
   DateTimeFormat = global.Intl.DateTimeFormat;
 } else {
   const IntlPolyfill = require('intl');
-  require('intl/locale-data/jsonp/fr');
-
   DateTimeFormat = IntlPolyfill.DateTimeFormat;
+  require('intl/locale-data/jsonp/fr');
+  require('intl/locale-data/jsonp/en-US');
 }
 
 const DatePickerExampleInternational = () => (
-  <DatePicker
-    hintText="fr version"
-    DateTimeFormat={DateTimeFormat}
-    // Intl is supported by most modern browsers, see http://caniuse.com/#search=intl
-    // for browsers that don't support it use this polyfill https://github.com/andyearnshaw/Intl.js
-    wordings={{ok: 'OK', cancel: 'Annuler'}}
-    firstDayOfWeek={1}
-    locale="fr"
-  />
+  <div>
+    <DatePicker
+      hintText="fr locale"
+      DateTimeFormat={DateTimeFormat}
+      locale="fr"
+      wordings={{ok: 'OK', cancel: 'Annuler'}}
+    />
+    <DatePicker
+      hintText="en-US locale"
+      DateTimeFormat={DateTimeFormat}
+      locale="en-US"
+      firstDayOfWeek={0}
+    />
+    <DatePicker
+      hintText="Custom date format"
+      firstDayOfWeek={0}
+      formatDate={new DateTimeFormat('en-US', {
+        day: 'numeric',
+        month: 'long',
+        year: 'numeric',
+      }).format}
+    />
+  </div>
 );
 
 export default DatePickerExampleInternational;
diff --git a/docs/src/app/components/pages/components/DatePicker/Page.jsx b/docs/src/app/components/pages/components/DatePicker/Page.jsx
index 7fa9fd6b6bd7be..ccd666ab3a2db2 100644
--- a/docs/src/app/components/pages/components/DatePicker/Page.jsx
+++ b/docs/src/app/components/pages/components/DatePicker/Page.jsx
@@ -28,8 +28,12 @@ const descriptions = {
   controlled: '`DatePicker` can be implemented as a controlled input, where `value` is handled by state in the ' +
   'parent component.',
   disabledDates: '`DatePicker` can disable specific dates based on the return value of a callback.',
-  localised: 'Date Picker can be localised using the `locale` property, in this case in French. ' +
-  'Note that the buttons must be localised using the `wordings` property, and we set the `firstDayOfWeek` to Monday.',
+  localised: '`DatePicker` can be localised using the `locale` property. The first example is localised in French. ' +
+  'Note that the buttons must be separately localised using the `cancelLabel` and `okLabel` properties. \n\n' +
+  'The `firstDayOfWeek` property defaults to `1`, (Monday), so may also need to be set for the target locale. ' +
+  'The second example shows sets `firstDayOfWeek` to `0`, (Sunday), and `locale` to `en-US` which matches the ' +
+  'bahavior of the Date Picker prior to 0.15.0.\n\n' +
+  'The final example displays the resulting date in a custom format using the `formatDate` property.',
 };
 
 const DatePickerPage = () => (
diff --git a/src/date-picker/date-picker.jsx b/src/date-picker/date-picker.jsx
index 638d6a8863f6b2..3405e81fd21bcc 100644
--- a/src/date-picker/date-picker.jsx
+++ b/src/date-picker/date-picker.jsx
@@ -8,8 +8,10 @@ const DatePicker = React.createClass({
 
   propTypes: {
     /**
-     * Constructor for time formatting.
-     * Follow this specification: ECMAScript Internationalization API 1.0 (ECMA-402).
+     * Constructor for date formatting for the specified `locale`.
+     * The constructor must follow this specification: ECMAScript Internationalization API 1.0 (ECMA-402).
+     * `Intl.DateTimeFormat` is supported by most modern browsers, see http://caniuse.com/#search=intl,
+     * otherwise https://github.com/andyearnshaw/Intl.js is a good polyfill.
      */
     DateTimeFormat: React.PropTypes.func,
 
@@ -43,23 +45,24 @@ const DatePicker = React.createClass({
     disabled: React.PropTypes.bool,
 
     /**
-     * Used to change the first day of week. It drastically varies from
-     * Saturday to Monday (could even be Friday) between different locales.
+     * Used to change the first day of week. It varies from
+     * Saturday to Monday between different locales.
      * The allowed range is 0 (Sunday) to 6 (Saturday).
+     * The default is `1`, Monday, as per ISO 8601.
      */
     firstDayOfWeek: React.PropTypes.number,
 
     /**
-     * This function is called to format the date to display in the input box.
-     * By default, date objects are formatted to MM/DD/YYYY.
+     * This function is called to format the date displayed in the input box, and should return a string.
+     * By default if no `locale` and `DateTimeFormat` is provided date objects are formatted to ISO 8601 YYYY-MM-DD.
+     *
+     * @param {object} date `Date` object to be formatted.
      */
     formatDate: React.PropTypes.func,
 
     /**
-     * Locale used for formatting date. If you are not using the default value, you
-     * have to provide a DateTimeFormat that supports it. You can use Intl.DateTimeFormat
-     * if it's supported by your environment.
-     * https://github.com/andyearnshaw/Intl.js is a good polyfill.
+     * Locale used for formatting the dialog date strings. If you are not using the default value, you
+     * have to provide a `DateTimeFormat` that supports it.
      */
     locale: React.PropTypes.string,
 
@@ -88,17 +91,17 @@ const DatePicker = React.createClass({
     onChange: React.PropTypes.func,
 
     /**
-     * Fired when the datepicker dialog is dismissed.
+     * Fired when the Date Picker dialog is dismissed.
      */
     onDismiss: React.PropTypes.func,
 
     /**
-     * Callback function that is fired when the datepicker field gains focus.
+     * Fired when the Date Picker field gains focus.
      */
     onFocus: React.PropTypes.func,
 
     /**
-     * Fired when the datepicker dialog is shown.
+     * Fired when the Date Picker dialog is shown.
      */
     onShow: React.PropTypes.func,
 
@@ -109,7 +112,7 @@ const DatePicker = React.createClass({
 
     /**
      * Called during render time of a given day. If this method returns
-     * false the day is disabled otherwise it is displayed normally.
+     * false the day is disabled, otherwise it is displayed normally.
      */
     shouldDisableDate: React.PropTypes.func,
 
@@ -149,11 +152,10 @@ const DatePicker = React.createClass({
 
   getDefaultProps() {
     return {
-      formatDate: DateTime.format,
       autoOk: false,
       disableYearSelection: false,
       style: {},
-      firstDayOfWeek: 0,
+      firstDayOfWeek: 1,
       disabled: false,
     };
   },
@@ -244,6 +246,18 @@ const DatePicker = React.createClass({
     }
   },
 
+  _formatDate(date) {
+    if (this.props.locale && this.props.DateTimeFormat) {
+      return new this.props.DateTimeFormat(this.props.locale, {
+        day: 'numeric',
+        month: 'numeric',
+        year: 'numeric',
+      }).format(date);
+    } else {
+      return DateTime.format(date);
+    }
+  },
+
   render() {
     const {
       container,
@@ -252,7 +266,6 @@ const DatePicker = React.createClass({
       wordings,
       autoOk,
       defaultDate,
-      formatDate,
       maxDate,
       minDate,
       mode,
@@ -268,9 +281,8 @@ const DatePicker = React.createClass({
       ...other,
     } = this.props;
 
-    const {
-      prepareStyles,
-    } = this.state.muiTheme;
+    const formatDate = this.props.formatDate || this._formatDate;
+    const {prepareStyles} = this.state.muiTheme;
 
     return (
       <div style={prepareStyles(Object.assign({}, style))}>
diff --git a/src/utils/date-time.js b/src/utils/date-time.js
index eb08dd3a42eaa9..c7be41cd667192 100644
--- a/src/utils/date-time.js
+++ b/src/utils/date-time.js
@@ -134,11 +134,9 @@ export default {
     return weekdayFormatter.format(this.addDays(firstDayDate, day + firstDayOfWeek));
   },
 
+  // Convert date to ISO8601 (YYYY-MM-DD) date string, accounting for current timezone
   format(date) {
-    const m = date.getMonth() + 1;
-    const d = date.getDate();
-    const y = date.getFullYear();
-    return `${m}/${d}/${y}`;
+    return (new Date(`${date.toDateString()} 12:00:00 +0000`)).toISOString().substring(0, 10);
   },
 
   /**