diff --git a/src/components/monitor/default-monitor.jsx b/src/components/monitor/default-monitor.jsx
index 992014775..3368519dd 100644
--- a/src/components/monitor/default-monitor.jsx
+++ b/src/components/monitor/default-monitor.jsx
@@ -10,7 +10,10 @@ const DefaultMonitor = ({categoryColor, label, value}) => (
             </div>
             <div
                 className={styles.value}
-                style={{background: categoryColor}}
+                style={{
+                    background: categoryColor.background,
+                    color: categoryColor.text
+                }}
             >
                 {value}
             </div>
@@ -19,7 +22,10 @@ const DefaultMonitor = ({categoryColor, label, value}) => (
 );
 
 DefaultMonitor.propTypes = {
-    categoryColor: PropTypes.string.isRequired,
+    categoryColor: PropTypes.shape({
+        background: PropTypes.string.isRequired,
+        text: PropTypes.string.isRequired
+    }).isRequired,
     label: PropTypes.string.isRequired,
     value: PropTypes.oneOfType([
         PropTypes.string,
diff --git a/src/components/monitor/large-monitor.jsx b/src/components/monitor/large-monitor.jsx
index 5101ad0a5..64ac32640 100644
--- a/src/components/monitor/large-monitor.jsx
+++ b/src/components/monitor/large-monitor.jsx
@@ -6,7 +6,10 @@ const LargeMonitor = ({categoryColor, value}) => (
     <div className={styles.largeMonitor}>
         <div
             className={styles.largeValue}
-            style={{background: categoryColor}}
+            style={{
+                background: categoryColor.background,
+                color: categoryColor.text
+            }}
         >
             {value}
         </div>
@@ -14,7 +17,10 @@ const LargeMonitor = ({categoryColor, value}) => (
 );
 
 LargeMonitor.propTypes = {
-    categoryColor: PropTypes.string,
+    categoryColor: PropTypes.shape({
+        background: PropTypes.string.isRequired,
+        text: PropTypes.string.isRequired
+    }).isRequired,
     value: PropTypes.oneOfType([
         PropTypes.string,
         PropTypes.number
diff --git a/src/components/monitor/list-monitor-scroller.jsx b/src/components/monitor/list-monitor-scroller.jsx
index cfcd6a248..ea0de244e 100644
--- a/src/components/monitor/list-monitor-scroller.jsx
+++ b/src/components/monitor/list-monitor-scroller.jsx
@@ -41,7 +41,10 @@ class ListMonitorScroller extends React.Component {
                 <div
                     className={styles.listValue}
                     dataIndex={index}
-                    style={{background: this.props.categoryColor}}
+                    style={{
+                        background: this.props.categoryColor.background,
+                        color: this.props.categoryColor.text
+                    }}
                     onClick={this.props.draggable ? this.handleEventFactory(index) : null}
                 >
                     {this.props.draggable && this.props.activeIndex === index ? (
@@ -51,6 +54,7 @@ class ListMonitorScroller extends React.Component {
                                 autoComplete={false}
                                 className={classNames(styles.listInput, 'no-drag')}
                                 spellCheck={false}
+                                style={{color: this.props.categoryColor.text}}
                                 type="text"
                                 value={this.props.activeValue}
                                 onBlur={this.props.onDeactivate}
@@ -97,7 +101,10 @@ class ListMonitorScroller extends React.Component {
 ListMonitorScroller.propTypes = {
     activeIndex: PropTypes.number,
     activeValue: PropTypes.string,
-    categoryColor: PropTypes.string,
+    categoryColor: PropTypes.shape({
+        background: PropTypes.string.isRequired,
+        text: PropTypes.string.isRequired
+    }).isRequired,
     draggable: PropTypes.bool,
     height: PropTypes.number,
     onActivate: PropTypes.func,
diff --git a/src/components/monitor/list-monitor.jsx b/src/components/monitor/list-monitor.jsx
index e3422e5b3..4bd9a2563 100644
--- a/src/components/monitor/list-monitor.jsx
+++ b/src/components/monitor/list-monitor.jsx
@@ -54,7 +54,10 @@ const ListMonitor = ({draggable, label, width, height, value, onResizeMouseDown,
 
 ListMonitor.propTypes = {
     activeIndex: PropTypes.number,
-    categoryColor: PropTypes.string.isRequired,
+    categoryColor: PropTypes.shape({
+        background: PropTypes.string.isRequired,
+        text: PropTypes.string.isRequired
+    }).isRequired,
     draggable: PropTypes.bool.isRequired,
     height: PropTypes.number,
     label: PropTypes.string.isRequired,
diff --git a/src/components/monitor/monitor.css b/src/components/monitor/monitor.css
index 0947db638..a4011457a 100644
--- a/src/components/monitor/monitor.css
+++ b/src/components/monitor/monitor.css
@@ -42,7 +42,6 @@
     align-items: center;
     min-width: 40px;
     text-align: center;
-    color: white;
     margin: 0 5px;
     border-radius: calc($space / 2);
     padding: 0 2px;
@@ -55,7 +54,6 @@
     min-width: 3rem;
     padding: 0.1rem 0.25rem;
     text-align: center;
-    color: white;
     font-size: 1rem;
     white-space: pre-wrap;
     transform: translateZ(0); /* Fixes flickering in Safari */
@@ -115,7 +113,6 @@
 .list-value {
     min-width: 40px;
     text-align: left;
-    color: white;
     margin: 0 3px;
     border-radius: calc($space / 2);
     border: 1px solid $ui-black-transparent;
@@ -161,7 +158,6 @@
     padding: 3px 5px;
     border: 0;
     background: none;
-    color: $ui-white;
     outline: none;
     font-size: 0.75rem;
     font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
@@ -174,7 +170,6 @@
     padding: 0;
     padding-right: 5px;
     cursor: pointer;
-    color: $ui-white;
 }
 
 .add-button {
diff --git a/src/components/monitor/monitor.jsx b/src/components/monitor/monitor.jsx
index ddb2f2e57..d9ceb9269 100644
--- a/src/components/monitor/monitor.jsx
+++ b/src/components/monitor/monitor.jsx
@@ -10,17 +10,19 @@ import DefaultMonitor from './default-monitor.jsx';
 import LargeMonitor from './large-monitor.jsx';
 import SliderMonitor from '../../containers/slider-monitor.jsx';
 import ListMonitor from '../../containers/list-monitor.jsx';
+import {getColorsForTheme} from '../../lib/themes/index.js';
 
 import styles from './monitor.css';
 
-const categories = {
-    data: '#FF8C1A',
-    sensing: '#5CB1D6',
-    sound: '#CF63CF',
-    looks: '#9966FF',
-    motion: '#4C97FF',
-    list: '#FC662C',
-    extension: '#0FBD8C'
+// Map category name to color name used in scratch-blocks Blockly.Colours
+const categoryColorMap = {
+    data: 'data',
+    sensing: 'sensing',
+    sound: 'sounds',
+    looks: 'looks',
+    motion: 'motion',
+    list: 'data_lists',
+    extension: 'pen'
 };
 
 const modes = {
@@ -30,6 +32,14 @@ const modes = {
     list: ListMonitor
 };
 
+const getCategoryColor = (theme, category) => {
+    const colors = getColorsForTheme(theme);
+    return {
+        background: colors[categoryColorMap[category]].primary,
+        text: colors.text
+    };
+};
+
 const MonitorComponent = props => (
     <ContextMenuTrigger
         disable={!props.draggable}
@@ -49,7 +59,7 @@ const MonitorComponent = props => (
                 onDoubleClick={props.mode === 'list' || !props.draggable ? null : props.onNextMode}
             >
                 {React.createElement(modes[props.mode], {
-                    categoryColor: categories[props.category],
+                    categoryColor: getCategoryColor(props.theme, props.category),
                     ...props
                 })}
             </Box>
@@ -122,12 +132,10 @@ const MonitorComponent = props => (
 
 );
 
-MonitorComponent.categories = categories;
-
 const monitorModes = Object.keys(modes);
 
 MonitorComponent.propTypes = {
-    category: PropTypes.oneOf(Object.keys(categories)),
+    category: PropTypes.oneOf(Object.keys(categoryColorMap)),
     componentRef: PropTypes.func.isRequired,
     draggable: PropTypes.bool.isRequired,
     label: PropTypes.string.isRequired,
@@ -140,7 +148,8 @@ MonitorComponent.propTypes = {
     onSetModeToDefault: PropTypes.func,
     onSetModeToLarge: PropTypes.func,
     onSetModeToSlider: PropTypes.func,
-    onSliderPromptOpen: PropTypes.func
+    onSliderPromptOpen: PropTypes.func,
+    theme: PropTypes.string.isRequired
 };
 
 MonitorComponent.defaultProps = {
diff --git a/src/components/monitor/slider-monitor.jsx b/src/components/monitor/slider-monitor.jsx
index 0271b140a..2bda8f593 100644
--- a/src/components/monitor/slider-monitor.jsx
+++ b/src/components/monitor/slider-monitor.jsx
@@ -12,7 +12,10 @@ const SliderMonitor = ({categoryColor, isDiscrete, label, min, max, value, onSli
             </div>
             <div
                 className={styles.value}
-                style={{background: categoryColor}}
+                style={{
+                    background: categoryColor.background,
+                    color: categoryColor.text
+                }}
             >
                 {value}
             </div>
@@ -33,7 +36,10 @@ const SliderMonitor = ({categoryColor, isDiscrete, label, min, max, value, onSli
 );
 
 SliderMonitor.propTypes = {
-    categoryColor: PropTypes.string.isRequired,
+    categoryColor: PropTypes.shape({
+        background: PropTypes.string.isRequired,
+        text: PropTypes.string.isRequired
+    }).isRequired,
     isDiscrete: PropTypes.bool,
     label: PropTypes.string.isRequired,
     max: PropTypes.number,
diff --git a/src/containers/monitor.jsx b/src/containers/monitor.jsx
index b952a1836..eee63392e 100644
--- a/src/containers/monitor.jsx
+++ b/src/containers/monitor.jsx
@@ -213,6 +213,7 @@ class Monitor extends React.Component {
                     min={this.props.min}
                     mode={this.props.mode}
                     targetId={this.props.targetId}
+                    theme={this.props.theme}
                     width={this.props.width}
                     onDragEnd={this.handleDragEnd}
                     onExport={isList ? this.handleExport : null}
@@ -250,6 +251,7 @@ Monitor.propTypes = {
     resizeMonitorRect: PropTypes.func.isRequired,
     spriteName: PropTypes.string, // eslint-disable-line react/no-unused-prop-types
     targetId: PropTypes.string,
+    theme: PropTypes.string,
     toolboxXML: PropTypes.string, // eslint-disable-line react/no-unused-prop-types
     value: PropTypes.oneOfType([
         PropTypes.string,
@@ -264,8 +266,12 @@ Monitor.propTypes = {
     x: PropTypes.number,
     y: PropTypes.number
 };
+Monitor.defaultProps = {
+    theme: 'standard'
+};
 const mapStateToProps = state => ({
     monitorLayout: state.scratchGui.monitorLayout,
+    theme: state.scratchGui.theme.theme,
     // render on toolbox updates since changes to the blocks could affect monitor labels, i.e. updated locale
     toolboxXML: state.scratchGui.toolbox.toolboxXML,
     vm: state.scratchGui.vm
diff --git a/src/lib/themes/high-contrast.js b/src/lib/themes/high-contrast.js
index d7abd0674..dc77490b5 100644
--- a/src/lib/themes/high-contrast.js
+++ b/src/lib/themes/high-contrast.js
@@ -70,9 +70,6 @@ const blockColors = {
         tertiary: '#FF3355',
         quaternary: '#FFE5EA'
     },
-    // For productionizing: we should look into making this field be the color of the text on the blocks
-    // e.g. move and steps in move (10) steps, and rename this property below for controlling the text inside
-    // of inputs e.g. 10
     text: '#000000',
     textFieldText: '#000000', // Text inside of inputs e.g. 90 in [point in direction (90)]
     toolboxText: '#000000', // Toolbox text, color picker text (used to be #575E75)
diff --git a/test/unit/components/monitor-list.test.jsx b/test/unit/components/monitor-list.test.jsx
index 051632ea4..5a3cdf4b2 100644
--- a/test/unit/components/monitor-list.test.jsx
+++ b/test/unit/components/monitor-list.test.jsx
@@ -11,6 +11,9 @@ describe('MonitorListComponent', () => {
             monitors: {},
             savedMonitorPositions: {}
         },
+        theme: {
+            theme: 'standard'
+        },
         toolbox: {
             toolboxXML: ''
         },
diff --git a/test/unit/components/monitor.test.jsx b/test/unit/components/monitor.test.jsx
new file mode 100644
index 000000000..a60ca0923
--- /dev/null
+++ b/test/unit/components/monitor.test.jsx
@@ -0,0 +1,55 @@
+import React from 'react';
+import {shallow} from 'enzyme';
+import DefaultMonitor from '../../../src/components/monitor/default-monitor';
+import Monitor from '../../../src/components/monitor/monitor';
+
+jest.mock('../../../src/lib/themes/default-colors');
+jest.mock('../../../src/lib/themes/dark-mode');
+
+describe('Monitor Component', () => {
+    test('it selects the correct colors based on default theme', () => {
+        const noop = () => {};
+
+        const wrapper = shallow(<Monitor
+            category="motion"
+            // eslint-disable-next-line react/jsx-no-bind
+            componentRef={noop}
+            draggable={false}
+            label="My label"
+            mode="default"
+            // eslint-disable-next-line react/jsx-no-bind
+            onDragEnd={noop}
+            // eslint-disable-next-line react/jsx-no-bind
+            onNextMode={noop}
+            theme="standard"
+        />);
+
+        const defaultMonitor = wrapper.find(DefaultMonitor);
+
+        // selects colors from mock value in src/lib/themes/__mocks__/default-colors.js
+        expect(defaultMonitor.props().categoryColor).toEqual({background: '#111111', text: '#444444'});
+    });
+
+    test('it selects the correct colors based on dark mode theme', () => {
+        const noop = () => {};
+
+        const wrapper = shallow(<Monitor
+            category="motion"
+            // eslint-disable-next-line react/jsx-no-bind
+            componentRef={noop}
+            draggable={false}
+            label="My label"
+            mode="default"
+            // eslint-disable-next-line react/jsx-no-bind
+            onDragEnd={noop}
+            // eslint-disable-next-line react/jsx-no-bind
+            onNextMode={noop}
+            theme="dark-mode"
+        />);
+
+        const defaultMonitor = wrapper.find(DefaultMonitor);
+
+        // selects colors from mock value in src/lib/themes/__mocks__/dark-mode.js
+        expect(defaultMonitor.props().categoryColor).toEqual({background: '#AAAAAA', text: '#BBBBBB'});
+    });
+});