diff --git a/src/components/gui/gui.jsx b/src/components/gui/gui.jsx
index 5cbd88cbc..488e705e8 100644
--- a/src/components/gui/gui.jsx
+++ b/src/components/gui/gui.jsx
@@ -35,15 +35,18 @@ const messages = defineMessages({
 
 const GUIComponent = props => {
     const {
+        activeTabIndex,
         basePath,
+        blocksTabVisible,
         children,
-        intl,
+        costumesTabVisible,
         feedbackFormVisible,
-        vm,
-        previewInfoVisible,
+        intl,
         onExtensionButtonClick,
-        onTabSelect,
-        tabIndex,
+        onActivateTab,
+        previewInfoVisible,
+        soundsTabVisible,
+        vm,
         ...componentProps
     } = props;
     if (children) {
@@ -86,9 +89,10 @@ const GUIComponent = props => {
                         <Tabs
                             className={tabClassNames.tabs}
                             forceRenderTabPanel={true} // eslint-disable-line react/jsx-boolean-value
+                            selectedIndex={activeTabIndex}
                             selectedTabClassName={tabClassNames.tabSelected}
                             selectedTabPanelClassName={tabClassNames.tabPanelSelected}
-                            onSelect={onTabSelect}
+                            onSelect={onActivateTab}
                         >
                             <TabList className={tabClassNames.tabList}>
                                 <Tab className={tabClassNames.tab}>Blocks</Tab>
@@ -99,7 +103,7 @@ const GUIComponent = props => {
                                 <Box className={styles.blocksWrapper}>
                                     <Blocks
                                         grow={1}
-                                        isVisible={tabIndex === 0} // Blocks tab
+                                        isVisible={blocksTabVisible}
                                         options={{
                                             media: `${basePath}static/blocks-media/`
                                         }}
@@ -121,10 +125,10 @@ const GUIComponent = props => {
                                 </Box>
                             </TabPanel>
                             <TabPanel className={tabClassNames.tabPanel}>
-                                {tabIndex === 1 ? <CostumeTab vm={vm} /> : null}
+                                {costumesTabVisible ? <CostumeTab vm={vm} /> : null}
                             </TabPanel>
                             <TabPanel className={tabClassNames.tabPanel}>
-                                {tabIndex === 2 ? <SoundTab vm={vm} /> : null}
+                                {soundsTabVisible ? <SoundTab vm={vm} /> : null}
                             </TabPanel>
                         </Tabs>
                     </Box>
@@ -159,14 +163,17 @@ const GUIComponent = props => {
     );
 };
 GUIComponent.propTypes = {
+    activeTabIndex: PropTypes.number,
     basePath: PropTypes.string,
+    blocksTabVisible: PropTypes.bool,
     children: PropTypes.node,
+    costumesTabVisible: PropTypes.bool,
     feedbackFormVisible: PropTypes.bool,
     intl: intlShape.isRequired,
+    onActivateTab: PropTypes.func,
     onExtensionButtonClick: PropTypes.func,
-    onTabSelect: PropTypes.func,
     previewInfoVisible: PropTypes.bool,
-    tabIndex: PropTypes.number,
+    soundsTabVisible: PropTypes.bool,
     vm: PropTypes.instanceOf(VM).isRequired
 };
 GUIComponent.defaultProps = {
diff --git a/src/containers/gui.jsx b/src/containers/gui.jsx
index d986e0d28..bae6f9684 100644
--- a/src/containers/gui.jsx
+++ b/src/containers/gui.jsx
@@ -2,23 +2,21 @@ import AudioEngine from 'scratch-audio';
 import PropTypes from 'prop-types';
 import React from 'react';
 import VM from 'scratch-vm';
-import bindAll from 'lodash.bindall';
 import {connect} from 'react-redux';
 
-import {openExtensionLibrary} from '../reducers/modals.js';
+import {openExtensionLibrary} from '../reducers/modals';
+import {
+    activateTab,
+    BLOCKS_TAB_INDEX,
+    COSTUMES_TAB_INDEX,
+    SOUNDS_TAB_INDEX
+} from '../reducers/editor-tab';
 
 import vmListenerHOC from '../lib/vm-listener-hoc.jsx';
 
 import GUIComponent from '../components/gui/gui.jsx';
 
 class GUI extends React.Component {
-    constructor (props) {
-        super(props);
-        bindAll(this, [
-            'handleTabSelect'
-        ]);
-        this.state = {tabIndex: 0};
-    }
     componentDidMount () {
         this.audioEngine = new AudioEngine();
         this.props.vm.attachAudioEngine(this.audioEngine);
@@ -34,9 +32,6 @@ class GUI extends React.Component {
     componentWillUnmount () {
         this.props.vm.stopAll();
     }
-    handleTabSelect (tabIndex) {
-        this.setState({tabIndex});
-    }
     render () {
         const {
             children,
@@ -46,9 +41,7 @@ class GUI extends React.Component {
         } = this.props;
         return (
             <GUIComponent
-                tabIndex={this.state.tabIndex}
                 vm={vm}
-                onTabSelect={this.handleTabSelect}
                 {...componentProps}
             >
                 {children}
@@ -68,12 +61,17 @@ GUI.propTypes = {
 GUI.defaultProps = GUIComponent.defaultProps;
 
 const mapStateToProps = state => ({
+    activeTabIndex: state.editorTab.activeTabIndex,
+    blocksTabVisible: state.editorTab.activeTabIndex === BLOCKS_TAB_INDEX,
+    costumesTabVisible: state.editorTab.activeTabIndex === COSTUMES_TAB_INDEX,
     feedbackFormVisible: state.modals.feedbackForm,
-    previewInfoVisible: state.modals.previewInfo
+    previewInfoVisible: state.modals.previewInfo,
+    soundsTabVisible: state.editorTab.activeTabIndex === SOUNDS_TAB_INDEX
 });
 
 const mapDispatchToProps = dispatch => ({
-    onExtensionButtonClick: () => dispatch(openExtensionLibrary())
+    onExtensionButtonClick: () => dispatch(openExtensionLibrary()),
+    onActivateTab: tab => dispatch(activateTab(tab))
 });
 
 const ConnectedGUI = connect(
diff --git a/src/reducers/editor-tab.js b/src/reducers/editor-tab.js
new file mode 100644
index 000000000..21b3534e2
--- /dev/null
+++ b/src/reducers/editor-tab.js
@@ -0,0 +1,37 @@
+const ACTIVATE_TAB = 'scratch-gui/navigation/ACTIVATE_TAB';
+
+// Constants use numbers to make it easier to work with react-tabs
+const BLOCKS_TAB_INDEX = 0;
+const COSTUMES_TAB_INDEX = 1;
+const SOUNDS_TAB_INDEX = 2;
+
+const initialState = {
+    activeTabIndex: BLOCKS_TAB_INDEX
+};
+
+const reducer = function (state, action) {
+    if (typeof state === 'undefined') state = initialState;
+    switch (action.type) {
+    case ACTIVATE_TAB:
+        return Object.assign({}, state, {
+            activeTabIndex: action.activeTabIndex
+        });
+    default:
+        return state;
+    }
+};
+
+const activateTab = function (tab) {
+    return {
+        type: ACTIVATE_TAB,
+        activeTabIndex: tab
+    };
+};
+
+export {
+    reducer as default,
+    activateTab,
+    BLOCKS_TAB_INDEX,
+    COSTUMES_TAB_INDEX,
+    SOUNDS_TAB_INDEX
+};
diff --git a/src/reducers/gui.js b/src/reducers/gui.js
index d49144b4f..d19966837 100644
--- a/src/reducers/gui.js
+++ b/src/reducers/gui.js
@@ -9,11 +9,13 @@ import targetReducer from './targets';
 import toolboxReducer from './toolbox';
 import vmReducer from './vm';
 import stageSizeReducer from './stage-size';
+import editorTabReducer from './editor-tab';
 import {ScratchPaintReducer} from 'scratch-paint';
 
 export default combineReducers({
     colorPicker: colorPickerReducer,
     customProcedures: customProceduresReducer,
+    editorTab: editorTabReducer,
     intl: intlReducer,
     stageSize: stageSizeReducer,
     modals: modalReducer,