diff --git a/tests/javascripts/radioSelect.test.js b/tests/javascripts/radioSelect.test.js
new file mode 100644
index 000000000..1e93de4e6
--- /dev/null
+++ b/tests/javascripts/radioSelect.test.js
@@ -0,0 +1,278 @@
+const helpers = require('./support/helpers');
+
+beforeAll(() => {
+  window.Hogan = require('hogan.js');
+  require('../../app/assets/javascripts/radioSelect.js');
+});
+
+afterAll(() => {
+  require('./support/teardown.js');
+});
+
+describe('RadioSelect', () => {
+  const CATEGORIES = [
+    'Later today',
+    'Tomorrow',
+    'Friday',
+    'Saturday'
+  ];
+  const HOURS = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24];
+  let originalOptionsForAllCategories;
+
+  const getDataFromOption = (option) => {
+    return {
+              value: option.querySelector('input').getAttribute('value'),
+              label: option.querySelector('label').textContent.trim()
+           };
+  };
+
+  const clickButtonForCategory = (category) => {
+
+    // click the button for this category
+    const categoryButton = document.querySelector(`.radio-select-column:nth-child(2) input[value="${category}"]`);
+    helpers.triggerEvent(categoryButton, 'click');
+
+  };
+
+  beforeEach(() => {
+    const options = () => {
+      let result = '';
+
+      const getHourLabel = (hour) => {
+        let label = hour;
+
+        if (hour === 12) {
+          return 'midday';
+        }
+
+        if (hour === 24) {
+          return 'midnight';
+        }
+
+        return `${hour}${hour > 12 ? 'am' : 'pm'}`;
+      };
+
+      const hours = (day, start) => {
+        let result = '';
+        let hours = HOURS;
+        let dayAsNumber = {
+          'Later today': 22,
+          'Tomorrow': 23,
+          'Friday': 24,
+          'Saturday': 25
+        }[day];
+
+        if (start !== undefined) {
+          hours = hours.slice(start - 1);
+        }
+
+        hours.forEach((hour, idx) => {
+          const hourLabel = getHourLabel(hour);
+
+          result +=
+            `<div class="multiple-choice">
+              <input id="scheduled_for-${idx}" name="scheduled_for" type="radio" value="2019-05-${dayAsNumber}T${hour}:00:00.459156">
+              <label for="scheduled_for-${idx}">
+                ${day} at ${hourLabel}
+              </label>
+            </div>`;
+        });
+
+        return result;
+      };
+
+      CATEGORIES.forEach((day, idx) => {
+        if (idx === 0) {
+          result += hours(day, 11);
+        } else {
+          result += hours(day);
+        }
+
+        return result;
+      });
+
+      return result;
+    };
+
+    document.body.innerHTML = `
+      <fieldset>
+        <legend class="form-label">
+          When should Notify send these messages?
+        </legend>
+        <div class="radio-select" data-module="radio-select" data-categories="${CATEGORIES.join(',')}">
+          <div class="radio-select-column">
+            <div class="multiple-choice">
+              <input checked="" id="scheduled_for-0" name="scheduled_for" type="radio" value="">
+              <label for="scheduled_for-0">
+                Now
+              </label>
+            </div>
+          </div>
+          <div class="radio-select-column">
+          ${options()}
+          </div>
+        </div>
+      </fieldset>`;
+
+      originalOptionsForAllCategories = Array.from(document.querySelector('.radio-select-column:nth-child(2) .multiple-choice'))
+                                          .map(option => getDataFromOption(option));
+  });
+
+  afterEach(() => {
+    document.body.innerHTML = '';
+  });
+
+  describe("when the page has loaded it should have a button for each category", () => {
+
+    let categoryButtons;
+
+    beforeEach(() => {
+
+      // start module
+      window.GOVUK.modules.start();
+
+      categoryButtons = document.querySelectorAll('.radio-select-column:nth-child(2) .js-category-button');
+
+    });
+
+    test("the number of buttons should match the categories", () => {
+
+      expect(categoryButtons.length).toBe(CATEGORIES.length);
+
+    });
+
+    test("each button's text should match their category", () => {
+
+      // check the buttons have the right text
+      CATEGORIES.forEach((category, idx) => {
+        expect(categoryButtons[idx].getAttribute('value')).toEqual(category);
+      });
+      
+    });
+
+  });
+
+  describe("category buttons", () => {
+
+    CATEGORIES.forEach((category, idx) => {
+
+      test(`clicking the button for ${category} should show the options for it, with the right label and value`, () => {
+
+        // get all the options in the original page for this category
+        originalOptionsForCategory = originalOptionsForAllCategories.filter(option => option.label === category);
+
+        // start module
+        window.GOVUK.modules.start();
+
+        clickButtonForCategory(category);
+
+        // check options this reveals against those originally in the page for this category
+        const options = document.querySelector('.radio-select-column:nth-child(2) .multiple-choice');
+
+        const optionsThatMatchOriginals = Array.from(options).filter((option, idx) => {
+          const optionData = getDataFromOption(option);
+          const originalOption = originalOptionsForCategory[idx];
+          
+          return optionData.value === originalOption.value && optionData.label === originalOption.label;
+        });
+
+        expect(optionsThatMatchOriginals.length).toEqual(originalOptionsForCategory.length);
+
+      });
+
+    });
+
+    test(`clicking the button for a category should add a 'Done' button below its options`, () => {
+
+      // start module
+      window.GOVUK.modules.start();
+
+      clickButtonForCategory(CATEGORIES[0]);
+
+      const button = document.querySelector('.radio-select-column:nth-child(2) input[type=button]');
+
+      expect(button).not.toBeNull();
+      expect(button.getAttribute('value')).toEqual('Done');
+
+    });
+
+  });
+
+  describe("after clicking the button to select that category", () => {
+
+    beforeEach(() => {
+
+      // start module
+      window.GOVUK.modules.start();
+
+      clickButtonForCategory(CATEGORIES[0]);
+
+    });
+
+    test("clicking the 'Done' button should reset the module to its initial state, showing the category buttons again", () => {
+
+      const doneButton = document.querySelector('.radio-select-column:nth-child(2) input[type=button]');
+
+      helpers.triggerEvent(doneButton, 'click');
+
+    });
+
+    describe("clicking on an option should", () => {
+
+      let optionsColumn;
+      let firstOptionLabel;
+
+      beforeEach(() => {
+
+        optionsColumn = document.querySelector('.radio-select-column:nth-child(2)');
+
+        const firstOption = optionsColumn.querySelector('input[type=radio]');
+        firstOptionLabel = firstOption.parentNode.querySelector('label').textContent.trim();
+
+        helpers.triggerEvent(firstOption, 'click');
+
+      });
+
+      test("remove all the other options", () => {
+
+        // module replaces the column node so this needs querying again
+        optionsColumn = document.querySelector('.radio-select-column:nth-child(2)');
+
+        expect(optionsColumn.querySelectorAll('input[type=radio]').length).toEqual(1);
+        expect(optionsColumn.querySelector('label').textContent.trim()).toEqual(firstOptionLabel);
+
+      });
+
+      test("add a button for choosing a different time", () => {
+
+        const button = document.querySelector('.radio-select-column:nth-child(3) input[type=button]');
+
+        expect(button).not.toBeNull();
+        expect(button.getAttribute('value')).toEqual('Choose a different time');
+
+      })
+
+    });
+
+    describe("after selecting an option", () => {
+
+      test("clicking the 'Choose a different time' button should reset the module", () => {
+
+        // select the first option
+        const firstOption = document.querySelector('.radio-select-column:nth-child(2) input[type=radio]');
+        helpers.triggerEvent(firstOption, 'click');
+
+        // click the 'Choose a different time' button
+        const resetButton = document.querySelector('.radio-select-column:nth-child(3) input[type=button]');
+        helpers.triggerEvent(resetButton, 'click');
+
+        categoryButtons = document.querySelectorAll('.radio-select-column:nth-child(2) .js-category-button');
+
+        expect(categoryButtons.length).toEqual(CATEGORIES.length);
+
+      });
+    });
+
+  });
+
+});