diff --git a/h5p.classes.php b/h5p.classes.php
index 5ede697..395e7a4 100644
--- a/h5p.classes.php
+++ b/h5p.classes.php
@@ -1664,6 +1664,8 @@ class H5PCore {
   );
   public static $styles = array(
     'styles/h5p.css',
+    'styles/h5p-confirmation-dialog.css',
+    'styles/h5p-core-button.css'
   );
   public static $scripts = array(
     'js/jquery.js',
@@ -1672,6 +1674,7 @@ class H5PCore {
     'js/h5p-x-api-event.js',
     'js/h5p-x-api.js',
     'js/h5p-content-type.js',
+    'js/h5p-confirmation-dialog.js'
   );
   public static $adminScripts = array(
     'js/jquery.js',
diff --git a/js/h5p-confirmation-dialog.js b/js/h5p-confirmation-dialog.js
new file mode 100644
index 0000000..7675d06
--- /dev/null
+++ b/js/h5p-confirmation-dialog.js
@@ -0,0 +1,162 @@
+/*global H5P*/
+H5P.ConfirmationDialog = (function (EventDispatcher) {
+  "use strict";
+
+  /**
+   * Create a confirmation dialog
+   *
+   * @param [options] Options for confirmation dialog
+   * @param [options.headerText] Header text
+   * @param [options.dialogText] Dialog text
+   * @param [options.cancelText] Cancel dialog button text
+   * @param [options.confirmText] Confirm dialog button text
+   * @constructor
+   */
+  function ConfirmationDialog(options) {
+    EventDispatcher.call(this);
+    var self = this;
+
+    // Default options
+    options = options || {};
+    options.headerText = options.headerText ||
+      'Confirm action';
+    options.dialogText = options.dialogText ||
+      'Please confirm that you wish to proceed. This action will not be reversible.';
+    options.cancelText = options.cancelText || 'Cancel';
+    options.confirmText = options.confirmText || 'Confirm';
+
+    // Create background
+    var popupBackground = document.createElement('div');
+    popupBackground.classList
+      .add('h5p-confirmation-dialog-background', 'hidden', 'hiding');
+
+    // Create outer popup
+    var popup = document.createElement('div');
+    popup.classList.add('h5p-confirmation-dialog-popup', 'hidden');
+    popupBackground.appendChild(popup);
+
+    // Popup header
+    var header = document.createElement('div');
+    header.classList.add('h5p-confirmation-dialog-header');
+    popup.appendChild(header);
+
+    // Header text
+    var headerText = document.createElement('div');
+    headerText.classList.add('h5p-confirmation-dialog-header-text');
+    headerText.innerHTML = options.headerText;
+    header.appendChild(headerText);
+
+    // Popup body
+    var body = document.createElement('div');
+    body.classList.add('h5p-confirmation-dialog-body');
+    popup.appendChild(body);
+
+    // Popup text
+    var text = document.createElement('div');
+    text.classList.add('h5p-confirmation-dialog-text');
+    text.innerHTML = options.dialogText;
+    body.appendChild(text);
+
+    // Popup buttons
+    var buttons = document.createElement('div');
+    buttons.classList.add('h5p-confirmation-dialog-buttons');
+    body.appendChild(buttons);
+
+    // Cancel button
+    var cancelButton = document.createElement('button');
+    cancelButton.classList.add('h5p-core-cancel-button');
+    cancelButton.tabindex = 0;
+    cancelButton.textContent = options.cancelText;
+    cancelButton.onclick = function () {
+      self.hide();
+      self.trigger('canceled');
+    };
+    buttons.appendChild(cancelButton);
+
+    // Confirm button
+    var confirmButton = document.createElement('button');
+    confirmButton.classList.add('h5p-core-button',
+      'h5p-confirmation-dialog-confirm-button');
+    confirmButton.tabindex = 0;
+    confirmButton.textContent = options.confirmText;
+    confirmButton.onclick = function () {
+      self.hide();
+      self.trigger('confirmed');
+    };
+    buttons.appendChild(confirmButton);
+
+    // Exit button
+    var exitButton = document.createElement('button');
+    exitButton.classList.add('h5p-confirmation-dialog-exit');
+    exitButton.tabindex = 0;
+    exitButton.onclick = function () {
+      self.hide();
+      self.trigger('canceled');
+    };
+    popup.appendChild(exitButton);
+
+    // Wrapper element
+    var wrapperElement;
+
+    /**
+     * Append confirmation dialog
+     * @param {HTMLElement} wrapper
+     * @returns {H5P.ConfirmationDialog}
+     */
+    this.appendTo = function (wrapper) {
+      wrapper.appendChild(popupBackground);
+      wrapperElement = wrapper;
+
+      return this;
+    };
+
+    /**
+     * Fit popup to container. Makes sure it doesn't overflow.
+     */
+    var fitToContainer = function () {
+      var popupOffset = parseInt(popup.style.top, 10) + popup.offsetHeight;
+
+      // Overflows wrapper
+      if (popupOffset > wrapperElement.offsetHeight) {
+        var overflowedContainerOffset = wrapperElement.offsetHeight - popup.offsetHeight;
+        popup.style.top = overflowedContainerOffset + 'px';
+      }
+    };
+
+    /**
+     * Show confirmation dialog
+     * @params {number} offsetTop Offset top
+     * @returns {H5P.ConfirmationDialog}
+     */
+    this.show = function (offsetTop) {
+      popup.style.top = offsetTop + 'px';
+      popupBackground.classList.remove('hidden');
+      fitToContainer();
+      popupBackground.classList.remove('hiding');
+      popup.classList.remove('hidden');
+      cancelButton.focus();
+
+      return this;
+    };
+
+    /**
+     * Hide confirmation dialog
+     * @returns {H5P.ConfirmationDialog}
+     */
+    this.hide = function () {
+      popupBackground.classList.add('hiding');
+      popup.classList.add('hidden');
+      setTimeout(function () {
+        popupBackground.classList.add('hidden');
+      }, 100);
+
+      return this;
+    };
+  }
+
+  ConfirmationDialog.prototype = Object.create(EventDispatcher.prototype);
+  ConfirmationDialog.prototype.constructor = ConfirmationDialog;
+
+  return ConfirmationDialog;
+
+}(H5P.EventDispatcher));
diff --git a/js/h5p-event-dispatcher.js b/js/h5p-event-dispatcher.js
index fb8dd66..592e8cf 100644
--- a/js/h5p-event-dispatcher.js
+++ b/js/h5p-event-dispatcher.js
@@ -99,7 +99,7 @@ H5P.EventDispatcher = (function () {
      *   Event type
      * @param {H5P.EventCallback} listener
      *   Event listener
-     * @param {Object} thisArg
+     * @param {Object} [thisArg]
      *   Optionally specify the this value when calling listener.
      */
     this.on = function (type, listener, thisArg) {
diff --git a/styles/h5p-confirmation-dialog.css b/styles/h5p-confirmation-dialog.css
new file mode 100644
index 0000000..b7b4475
--- /dev/null
+++ b/styles/h5p-confirmation-dialog.css
@@ -0,0 +1,103 @@
+.h5p-confirmation-dialog-background {
+  position: absolute;
+  height: 100%;
+  width: 100%;
+  left: 0;
+  top: 0;
+
+  background: rgba(255, 255, 255, 0.85);
+  opacity: 1;
+  visibility: visible;
+  -webkit-transition: opacity 0.1s, linear 0s, visibility 0s linear 0s;
+  transition: opacity 0.1s linear 0s, visibility 0s linear 0s;
+
+  z-index: 11;
+}
+
+.h5p-confirmation-dialog-background.hidden {
+  display: none;
+}
+
+.h5p-confirmation-dialog-background.hiding {
+  opacity: 0;
+  visibility: hidden;
+  -webkit-transition: opacity 0.1s, linear 0s, visibility 0s linear 0.1s;
+  transition: opacity 0.1s linear 0s, visibility 0s linear 0.1s;
+}
+
+.h5p-confirmation-dialog-popup {
+  position: absolute;
+  display: flex;
+  flex-direction: column;
+  justify-content: center;
+
+  box-sizing: border-box;
+  max-width: calc(100% - 2em);
+  min-width: 25em;
+
+  top: 2em;
+  left: 50%;
+  -webkit-transform: translate(-50%, 0%);
+  -ms-transform: translate(-50%, 0%);
+  transform: translate(-50%, 0%);
+
+  color: #555;
+  box-shadow: 0 0 6px 1px #ddd;
+
+  -webkit-transition: transform 0.1s ease-in;
+  transition: transform 0.1s ease-in;
+}
+
+.h5p-confirmation-dialog-popup.hidden {
+  -webkit-transform: translate(-50%, 50%);
+  -ms-transform: translate(-50%, 50%);
+  transform: translate(-50%, 50%);
+}
+
+.h5p-confirmation-dialog-header {
+  padding: 1.5em;
+  background: #fff;
+  color: #1a73d9;
+}
+
+.h5p-confirmation-dialog-header-text {
+  font-size: 1.25em;
+}
+
+.h5p-confirmation-dialog-body {
+  padding: 1.25em 1.5em;
+  background: #fafafa;
+}
+
+.h5p-confirmation-dialog-text {
+  margin-bottom: 1.5em;
+}
+
+.h5p-confirmation-dialog-buttons {
+  float: right;
+}
+
+.h5p-confirmation-dialog-exit {
+  position: absolute;
+  background: none;
+  border: none;
+  font-size: 2.5em;
+  top: -0.9em;
+  right: -1.15em;
+  color: #777;
+  cursor: pointer;
+}
+
+.h5p-confirmation-dialog-exit:before {
+  font-family: "H5P";
+  content: "\e890";
+}
+
+.h5p-core-button.h5p-confirmation-dialog-confirm-button {
+  padding-left: 0.75em;
+  margin-bottom: 0;
+}
+
+.h5p-core-button.h5p-confirmation-dialog-confirm-button:before {
+  content: "\e601";
+}
diff --git a/styles/h5p-core-button.css b/styles/h5p-core-button.css
new file mode 100644
index 0000000..e073e74
--- /dev/null
+++ b/styles/h5p-core-button.css
@@ -0,0 +1,59 @@
+.h5p-core-button {
+  font-size: 1em;
+  line-height: 1.2;
+  padding: 0.5em 1.25em;
+  border-radius: 2em;
+
+  background: #1a73d9;
+  color: #ffffff;
+
+  cursor: pointer;
+  border: none;
+  box-shadow: none;
+  outline: none;
+
+  display: inline-block;
+  text-align: center;
+  text-shadow: none;
+  vertical-align: baseline;
+}
+.h5p-core-button:hover,
+.h5p-core-button:focus {
+  background: #1356a3;
+  color: #fff;
+  text-decoration: none;
+  -webkit-transition: initial;
+  transition: initial;
+}
+.h5p-core-button:active {
+  position: relative;
+  background: #104888;
+
+  -webkit-box-shadow: inset 0 4px 0 #0e407a;
+  -moz-box-shadow: inset 0 4px 0 #0e407a;
+  box-shadow: inset 0 4px 0 #0e407a;
+}
+
+.h5p-core-button:before {
+  font-family: 'H5P';
+  padding-right: 0.15em;
+  font-size: 1.5em;
+  vertical-align: middle;
+  line-height: 0.7;
+}
+
+.h5p-core-cancel-button {
+  cursor: pointer;
+  background: none;
+  border: none;
+  color: #a00;
+  margin-right: 1em;
+  font-size: 1em;
+}
+
+.h5p-core-cancel-button:hover,
+.h5p-core-cancel-button:focus {
+  background: none;
+  border: none;
+  color: #e40000;
+}