diff --git a/src/editor/pybricksMicroPython.ts b/src/editor/pybricksMicroPython.ts
index 37b18e05..c47e938c 100644
--- a/src/editor/pybricksMicroPython.ts
+++ b/src/editor/pybricksMicroPython.ts
@@ -253,42 +253,57 @@ export const language = <monaco.languages.IMonarchLanguage>{
     },
 };
 
-function template(hubName: string, devices: string[]): string {
-    return `from pybricks.hubs import ${hubName}
-from pybricks.pupdevices import ${devices.join(', ')}
+/**
+ * Creates a new template for the given parameters.
+ *
+ * @param hubClassName The hub class name, e.g. `"MoveHub"`.
+ * @param deviceClassNames A list of device class names, e.g. `["Motor"]`.
+ * @returns The template.
+ */
+function createTemplate(hubClassName: string, deviceClassNames: string[]): string {
+    return `from pybricks.hubs import ${hubClassName}
+from pybricks.pupdevices import ${deviceClassNames.join(', ')}
 from pybricks.parameters import Button, Color, Direction, Port, Stop
 from pybricks.robotics import DriveBase
 from pybricks.tools import wait, StopWatch
 
-hub = ${hubName}()
+hub = ${hubClassName}()
 
 `;
 }
 
+type HubLabel =
+    | 'movehub'
+    | 'cityhub'
+    | 'technichub'
+    | 'inventorhub'
+    | 'primehub'
+    | 'essentialhub';
+
 const templateSnippets: Array<
     Required<
         Pick<monaco.languages.CompletionItem, 'label' | 'documentation' | 'insertText'>
-    > & { label: string }
+    > & { label: HubLabel }
 > = [
     {
         label: 'technichub',
         documentation: 'Template for Technic hub program.',
-        insertText: template('TechnicHub', ['Motor']),
+        insertText: createTemplate('TechnicHub', ['Motor']),
     },
     {
         label: 'cityhub',
         documentation: 'Template for City hub program.',
-        insertText: template('CityHub', ['DCMotor', 'Light']),
+        insertText: createTemplate('CityHub', ['DCMotor', 'Light']),
     },
     {
         label: 'movehub',
         documentation: 'Template for BOOST Move hub program.',
-        insertText: template('MoveHub', ['Motor', 'ColorDistanceSensor']),
+        insertText: createTemplate('MoveHub', ['Motor', 'ColorDistanceSensor']),
     },
     {
         label: 'inventorhub',
         documentation: 'Template for MINDSTORMS Robot Inventor hub program.',
-        insertText: template('InventorHub', [
+        insertText: createTemplate('InventorHub', [
             'Motor',
             'ColorSensor',
             'UltrasonicSensor',
@@ -297,7 +312,7 @@ const templateSnippets: Array<
     {
         label: 'primehub',
         documentation: 'Template for SPIKE Prime program.',
-        insertText: template('PrimeHub', [
+        insertText: createTemplate('PrimeHub', [
             'Motor',
             'ColorSensor',
             'UltrasonicSensor',
@@ -307,7 +322,7 @@ const templateSnippets: Array<
     {
         label: 'essentialhub',
         documentation: 'Template for SPIKE Essential program.',
-        insertText: template('EssentialHub', [
+        insertText: createTemplate('EssentialHub', [
             'Motor',
             'ColorSensor',
             'ColorLightMatrix',
@@ -315,6 +330,14 @@ const templateSnippets: Array<
     },
 ];
 
+/**
+ * Gets the template text for a Pybricks MicroPython file.
+ * @param hub The hub label.
+ */
+export function getPybricksMicroPythonFileTemplate(hub: HubLabel): string | undefined {
+    return templateSnippets.find((t) => t.label === hub)?.insertText;
+}
+
 export const templateSnippetCompletions = <monaco.languages.CompletionItemProvider>{
     provideCompletionItems: (model, position, _context, _token) => {
         // templates snippets are only available on the first line
diff --git a/src/explorer/Explorer.test.tsx b/src/explorer/Explorer.test.tsx
index b75155ea..0805a31d 100644
--- a/src/explorer/Explorer.test.tsx
+++ b/src/explorer/Explorer.test.tsx
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: MIT
 // Copyright (c) 2022 The Pybricks Authors
 
+import { getByLabelText, waitFor } from '@testing-library/dom';
 import userEvent from '@testing-library/user-event';
 import React from 'react';
 import { testRender } from '../../test';
@@ -37,6 +38,22 @@ describe('archive button', () => {
     });
 });
 
+describe('new file button', () => {
+    it('should show new file wizard', async () => {
+        const [explorer] = testRender(<Explorer />);
+
+        const button = explorer.getByTitle('Create a new file');
+
+        userEvent.click(button);
+
+        const dialog = explorer.getByRole('dialog');
+        expect(dialog).toBeVisible();
+
+        userEvent.click(getByLabelText(dialog, 'Close'));
+        await waitFor(() => expect(dialog).not.toBeVisible());
+    });
+});
+
 describe('list item', () => {
     it('should show/hide buttons on hover', () => {
         const [explorer] = testRender(<Explorer />, {
diff --git a/src/explorer/Explorer.tsx b/src/explorer/Explorer.tsx
index 7fbe87c1..2343e6ad 100644
--- a/src/explorer/Explorer.tsx
+++ b/src/explorer/Explorer.tsx
@@ -20,6 +20,7 @@ import {
     fileStorageExportFile,
 } from '../fileStorage/actions';
 import { useSelector } from '../reducers';
+import NewFileWizard from './NewFileWizard';
 import { ExplorerStringId } from './i18n';
 import en from './i18n.en.json';
 
@@ -102,6 +103,7 @@ const FileActionButtonGroup = forwardRef<
 FileActionButtonGroup.displayName = 'FileActionButtonGroup';
 
 const Header: React.VFC = () => {
+    const [isNewFileWizardOpen, setIsNewFileWizardOpen] = useState(false);
     const dispatch = useDispatch();
     const fileNames = useSelector((s) => s.fileStorage.fileNames);
 
@@ -125,7 +127,11 @@ const Header: React.VFC = () => {
                 <ActionButton
                     icon="plus"
                     toolTipId={ExplorerStringId.HeaderAddNewTooltip}
-                    onClick={() => alert('not implemented')}
+                    onClick={() => setIsNewFileWizardOpen(true)}
+                />
+                <NewFileWizard
+                    isOpen={isNewFileWizardOpen}
+                    onClose={() => setIsNewFileWizardOpen(false)}
                 />
             </ButtonGroup>
         </div>
diff --git a/src/explorer/NewFileWizard.tsx b/src/explorer/NewFileWizard.tsx
new file mode 100644
index 00000000..729c0ea8
--- /dev/null
+++ b/src/explorer/NewFileWizard.tsx
@@ -0,0 +1,241 @@
+// SPDX-License-Identifier: MIT
+// Copyright (c) 2022 The Pybricks Authors
+
+import {
+    Button,
+    Classes,
+    Dialog,
+    FormGroup,
+    InputGroup,
+    Radio,
+    RadioGroup,
+    Tag,
+} from '@blueprintjs/core';
+import { useI18n } from '@shopify/react-i18n';
+import React, { useRef, useState } from 'react';
+import { useDispatch } from 'react-redux';
+import { useSelector } from '../reducers';
+import { FileExtension, Hub, explorerCreateNewFile } from './actions';
+import { NewFileWizardStringId } from './i18n';
+import en from './i18n.en.json';
+
+// This should be set to the most commonly used hub.
+const defaultHub = Hub.Technic;
+
+/** File name validation results. */
+enum FileNameValidationResult {
+    /** The file name is acceptable. */
+    IsOk,
+    /** The file name is an empty string. */
+    IsEmpty,
+    /** The file name contains spaces. */
+    HasSpaces,
+    /** The file name include the file file extension. */
+    HasFileExtension,
+    /** The first character is not a letter or underscore. */
+    HasInvalidFirstCharacter,
+    /** The file name has invalid characters. */
+    HasInvalidCharacters,
+    /** A file with the same name already exists. */
+    AlreadyExists,
+}
+
+/**
+ * Validates the file name according to a number of criteria.
+ *
+ * @param fileName The file name (without extension).
+ * @param extension The file extension (include ".").
+ * @param existingFiles List of existing files.
+ * @returns The result of the validation.
+ */
+function validateFileName(
+    fileName: string,
+    extension: string,
+    existingFiles: ReadonlyArray<string>,
+): FileNameValidationResult {
+    if (existingFiles.includes(`${fileName}${extension}`)) {
+        return FileNameValidationResult.AlreadyExists;
+    }
+
+    if (fileName.length === 0) {
+        return FileNameValidationResult.IsEmpty;
+    }
+
+    if (fileName.match(/\s/)) {
+        return FileNameValidationResult.HasSpaces;
+    }
+
+    if (fileName.endsWith(extension)) {
+        return FileNameValidationResult.HasFileExtension;
+    }
+
+    if (!fileName.match(/^[a-zA-Z_]/)) {
+        return FileNameValidationResult.HasInvalidFirstCharacter;
+    }
+
+    if (!fileName.match(/^[a-zA-Z0-9_-]+$/)) {
+        return FileNameValidationResult.HasInvalidCharacters;
+    }
+
+    return FileNameValidationResult.IsOk;
+}
+
+type FileNameHelpTextProps = {
+    validation: FileNameValidationResult;
+};
+
+/**
+ * Component that maps FileNameValidationResult to help message to display to user.
+ */
+const FileNameHelpText: React.VoidFunctionComponent<FileNameHelpTextProps> = (
+    props,
+) => {
+    const [i18n] = useI18n({ id: 'newFileWizard', translations: { en }, fallback: en });
+
+    switch (props.validation) {
+        case FileNameValidationResult.IsOk:
+            return <>{i18n.translate(NewFileWizardStringId.FileNameHelpTextIsOk)}</>;
+        case FileNameValidationResult.IsEmpty:
+            return <>{i18n.translate(NewFileWizardStringId.FileNameHelpTextIsEmpty)}</>;
+        case FileNameValidationResult.HasSpaces:
+            return (
+                <>{i18n.translate(NewFileWizardStringId.FileNameHelpTextHasSpaces)}</>
+            );
+        case FileNameValidationResult.HasFileExtension:
+            return (
+                <>
+                    {i18n.translate(
+                        NewFileWizardStringId.FileNameHelpTextHasFileExtension,
+                    )}
+                </>
+            );
+        case FileNameValidationResult.HasInvalidFirstCharacter:
+            return (
+                <>
+                    {i18n.translate(
+                        NewFileWizardStringId.FileNameHelpTextHasInvalidFirstCharacter,
+                        {
+                            letters: <code className={Classes.CODE}>a…z</code>,
+                            underscore: <code className={Classes.CODE}>_</code>,
+                        },
+                    )}
+                </>
+            );
+        case FileNameValidationResult.HasInvalidCharacters:
+            return (
+                <>
+                    {i18n.translate(
+                        NewFileWizardStringId.FileNameHelpTextHasInvalidCharacters,
+                        {
+                            letters: <code className={Classes.CODE}>a…z</code>,
+                            numbers: <code className={Classes.CODE}>0…9</code>,
+                            dash: <code className={Classes.CODE}>-</code>,
+                            underscore: <code className={Classes.CODE}>_</code>,
+                        },
+                    )}
+                </>
+            );
+        case FileNameValidationResult.AlreadyExists:
+            return (
+                <>
+                    {i18n.translate(
+                        NewFileWizardStringId.FileNameHelpTextAlreadyExists,
+                    )}
+                </>
+            );
+    }
+};
+
+type NewFileWizardProps = {
+    readonly isOpen: boolean;
+    readonly onClose: () => void;
+};
+
+const NewFileWizard: React.VoidFunctionComponent<NewFileWizardProps> = (props) => {
+    const [i18n] = useI18n({ id: 'newFileWizard', translations: { en }, fallback: en });
+    const dispatch = useDispatch();
+    const fileNames = useSelector((s) => s.fileStorage.fileNames);
+
+    const [fileName, setFileName] = useState('');
+    const [fileNameValidation, setFileNameValidation] = useState(
+        FileNameValidationResult.IsEmpty,
+    );
+    const [hubType, setHubType] = useState(defaultHub);
+
+    const fileNameInputRef = useRef<HTMLInputElement>(null);
+
+    const fileNameIntent =
+        fileNameValidation === FileNameValidationResult.IsOk ? 'none' : 'danger';
+
+    const handleFileNameChanged = (fileName: string) => {
+        setFileNameValidation(
+            validateFileName(fileName, FileExtension.Python, fileNames),
+        );
+        setFileName(fileName);
+    };
+
+    return (
+        <Dialog
+            icon="plus"
+            title={i18n.translate(NewFileWizardStringId.Title)}
+            isOpen={props.isOpen}
+            onOpening={() => handleFileNameChanged('')}
+            onOpened={() => fileNameInputRef.current?.focus()}
+            onClose={() => props.onClose()}
+        >
+            <div className={Classes.DIALOG_BODY}>
+                <FormGroup
+                    label={i18n.translate(NewFileWizardStringId.FileNameLabel)}
+                    intent={fileNameIntent}
+                    subLabel={<FileNameHelpText validation={fileNameValidation} />}
+                >
+                    <InputGroup
+                        aria-label="File name"
+                        value={fileName}
+                        inputRef={fileNameInputRef}
+                        intent={fileNameIntent}
+                        rightElement={<Tag>{FileExtension.Python}</Tag>}
+                        onChange={(e) => handleFileNameChanged(e.target.value)}
+                    />
+                </FormGroup>
+                <FormGroup label={i18n.translate(NewFileWizardStringId.SmartHubLabel)}>
+                    <RadioGroup
+                        selectedValue={hubType}
+                        onChange={(e) => setHubType(e.currentTarget.value as Hub)}
+                    >
+                        <Radio value={Hub.Move}>BOOST Move Hub</Radio>
+                        <Radio value={Hub.City}>City Hub</Radio>
+                        <Radio value={Hub.Technic}>Technic Hub</Radio>
+                        <Radio value={Hub.Prime}>SPIKE Prime</Radio>
+                        <Radio value={Hub.Essential}>SPIKE Essential</Radio>
+                        <Radio value={Hub.Inventor}>MINDSTORMS Robot Inventor</Radio>
+                    </RadioGroup>
+                </FormGroup>
+            </div>
+            <div className={Classes.DIALOG_FOOTER}>
+                <div className={Classes.DIALOG_FOOTER_ACTIONS}>
+                    <Button
+                        aria-label="Create"
+                        intent="primary"
+                        disabled={fileNameValidation !== FileNameValidationResult.IsOk}
+                        onMouseDown={(e) => e.preventDefault()}
+                        onClick={() => {
+                            props.onClose();
+                            dispatch(
+                                explorerCreateNewFile(
+                                    fileName,
+                                    FileExtension.Python,
+                                    hubType,
+                                ),
+                            );
+                        }}
+                    >
+                        {i18n.translate(NewFileWizardStringId.ActionCreate)}
+                    </Button>
+                </div>
+            </div>
+        </Dialog>
+    );
+};
+
+export default NewFileWizard;
diff --git a/src/explorer/NewFileWizart.test.tsx b/src/explorer/NewFileWizart.test.tsx
new file mode 100644
index 00000000..5ad3b1a6
--- /dev/null
+++ b/src/explorer/NewFileWizart.test.tsx
@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: MIT
+// Copyright (c) 2022 The Pybricks Authors
+
+import { waitFor } from '@testing-library/dom';
+import userEvent from '@testing-library/user-event';
+import React from 'react';
+import { testRender } from '../../test';
+import NewFileWizard from './NewFileWizard';
+
+describe('create button', () => {
+    it('should close the dialog', async () => {
+        const onClose = jest.fn();
+        const [dialog] = testRender(<NewFileWizard isOpen={true} onClose={onClose} />);
+
+        const button = dialog.getByLabelText('Create');
+
+        // have to type a file name before Create button is enabled
+        userEvent.type(dialog.getByLabelText('File name'), 'test');
+        await waitFor(() => expect(button).not.toBeDisabled());
+
+        userEvent.click(button);
+        expect(onClose).toHaveBeenCalled();
+    });
+});
diff --git a/src/explorer/actions.ts b/src/explorer/actions.ts
new file mode 100644
index 00000000..4f79e190
--- /dev/null
+++ b/src/explorer/actions.ts
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: MIT
+// Copyright (c) 2022 The Pybricks Authors
+
+import { createAction } from '../actions';
+
+/** Supported file extensions. */
+export enum FileExtension {
+    /** Python (.py) */
+    Python = '.py',
+}
+
+/** Supported hub types. */
+export enum Hub {
+    /** BOOST Move hub */
+    Move = 'movehub',
+    /** City hub */
+    City = 'cityhub',
+    /** Technic hub */
+    Technic = 'technichub',
+    /** MINDSTORMS Robot Inventor hub */
+    Inventor = 'inventorhub',
+    /** SPIKE Prime hub */
+    Prime = 'primehub',
+    /** SPIKE Essential hub */
+    Essential = 'essentialhub',
+}
+
+/**
+ * Action that requests to create a new file.
+ * @param fileName The requested new file name (without file extension).
+ * @param fileExtension The file extension (including leading ".").
+ * @param hub The type of hub this file is for.
+ */
+export const explorerCreateNewFile = createAction(
+    (fileName: string, fileExtension: FileExtension, hub: Hub) => ({
+        type: 'explorer.action.createNewFile',
+        fileName,
+        fileExtension,
+        hub,
+    }),
+);
diff --git a/src/explorer/i18n.en.json b/src/explorer/i18n.en.json
index ccd706f9..0dfcd595 100644
--- a/src/explorer/i18n.en.json
+++ b/src/explorer/i18n.en.json
@@ -10,5 +10,26 @@
             "exportTooltip": "Export {fileName}",
             "renameTooltip": "Rename {fileName}"
         }
+    },
+    "newFileWizard": {
+        "title": "Create a new file",
+        "fileName": {
+            "label": "File name",
+            "helpText": {
+                "isOk": "OK!",
+                "isEmpty": "File name cannot be empty.",
+                "hasSpaces": "File name cannot have spaces.",
+                "hasFileExtension": "The file extension will be added automatically.",
+                "hasInvalidFirstCharacter": "File name must start with a letter ({letters}) or underscore ({underscore}).",
+                "hasInvalidCharacters": "File name can only contain letters ({letters}), numbers ({numbers}), dashes ({dash}) and underscores ({underscore}).",
+                "alreadyExists": "A file with this name already exists."
+            }
+        },
+        "smartHub": {
+            "label": "Smart hub"
+        },
+        "action": {
+            "create": "Create"
+        }
     }
 }
diff --git a/src/explorer/i18n.test.ts b/src/explorer/i18n.test.ts
index ad68f26f..6c478b14 100644
--- a/src/explorer/i18n.test.ts
+++ b/src/explorer/i18n.test.ts
@@ -2,7 +2,7 @@
 // Copyright (c) 2022 The Pybricks Authors
 
 import { lookup } from '../../test';
-import { ExplorerStringId } from './i18n';
+import { ExplorerStringId, NewFileWizardStringId } from './i18n';
 import en from './i18n.en.json';
 
 describe('Ensure .json file has matches for ExplorerStringId', () => {
@@ -10,3 +10,9 @@ describe('Ensure .json file has matches for ExplorerStringId', () => {
         expect(lookup(en, id)).toBeDefined();
     });
 });
+
+describe('Ensure .json file has matches for NewFileWizardStringId', () => {
+    test.each(Object.values(NewFileWizardStringId))('%s', (id) => {
+        expect(lookup(en, id)).toBeDefined();
+    });
+});
diff --git a/src/explorer/i18n.ts b/src/explorer/i18n.ts
index 8a3502db..582bbc3f 100644
--- a/src/explorer/i18n.ts
+++ b/src/explorer/i18n.ts
@@ -11,3 +11,17 @@ export enum ExplorerStringId {
     TreeItemExportTooltip = 'explorer.treeItem.exportTooltip',
     TreeItemRenameTooltip = 'explorer.treeItem.renameTooltip',
 }
+
+export enum NewFileWizardStringId {
+    Title = 'newFileWizard.title',
+    FileNameLabel = 'newFileWizard.fileName.label',
+    FileNameHelpTextIsOk = 'newFileWizard.fileName.helpText.isOk',
+    FileNameHelpTextIsEmpty = 'newFileWizard.fileName.helpText.isEmpty',
+    FileNameHelpTextHasSpaces = 'newFileWizard.fileName.helpText.hasSpaces',
+    FileNameHelpTextHasFileExtension = 'newFileWizard.fileName.helpText.hasFileExtension',
+    FileNameHelpTextHasInvalidFirstCharacter = 'newFileWizard.fileName.helpText.hasInvalidFirstCharacter',
+    FileNameHelpTextHasInvalidCharacters = 'newFileWizard.fileName.helpText.hasInvalidCharacters',
+    FileNameHelpTextAlreadyExists = 'newFileWizard.fileName.helpText.alreadyExists',
+    SmartHubLabel = 'newFileWizard.smartHub.label',
+    ActionCreate = 'newFileWizard.action.create',
+}
diff --git a/src/explorer/sagas.test.ts b/src/explorer/sagas.test.ts
new file mode 100644
index 00000000..c5a0d101
--- /dev/null
+++ b/src/explorer/sagas.test.ts
@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: MIT
+// Copyright (c) 2022 The Pybricks Authors
+
+import { AsyncSaga } from '../../test';
+import { FileExtension, Hub, explorerCreateNewFile } from './actions';
+import explorer from './sagas';
+
+describe('handleExplorerCreateNewFile', () => {
+    it('should dispatch fileStorage action', async () => {
+        const saga = new AsyncSaga(explorer);
+
+        saga.put(explorerCreateNewFile('test', FileExtension.Python, Hub.Technic));
+
+        const action = await saga.take();
+        expect(action).toMatchInlineSnapshot(`
+            Object {
+              "fileContents": "from pybricks.hubs import TechnicHub
+            from pybricks.pupdevices import Motor
+            from pybricks.parameters import Button, Color, Direction, Port, Stop
+            from pybricks.robotics import DriveBase
+            from pybricks.tools import wait, StopWatch
+
+            hub = TechnicHub()
+
+            ",
+              "fileName": "test.py",
+              "type": "fileStorage.action.writeFile",
+            }
+        `);
+
+        await saga.end();
+    });
+});
diff --git a/src/explorer/sagas.ts b/src/explorer/sagas.ts
new file mode 100644
index 00000000..919a3299
--- /dev/null
+++ b/src/explorer/sagas.ts
@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: MIT
+// Copyright (c) 2022 The Pybricks Authors
+
+import { put, takeEvery } from 'typed-redux-saga/macro';
+import { getPybricksMicroPythonFileTemplate } from '../editor/pybricksMicroPython';
+import { fileStorageWriteFile } from '../fileStorage/actions';
+import { explorerCreateNewFile } from './actions';
+
+function* handleExplorerCreateNewFile(
+    action: ReturnType<typeof explorerCreateNewFile>,
+): Generator {
+    const fileName = `${action.fileName}${action.fileExtension}`;
+
+    yield* put(
+        fileStorageWriteFile(
+            fileName,
+            getPybricksMicroPythonFileTemplate(action.hub) || '',
+        ),
+    );
+}
+
+export default function* (): Generator {
+    yield* takeEvery(explorerCreateNewFile, handleExplorerCreateNewFile);
+}
diff --git a/src/sagas.ts b/src/sagas.ts
index 254f98c0..a9fe4e96 100644
--- a/src/sagas.ts
+++ b/src/sagas.ts
@@ -8,6 +8,7 @@ import blePybricksService from './ble-pybricks-service/sagas';
 import ble from './ble/sagas';
 import editor, { EditorSagaContext } from './editor/sagas';
 import errorLog from './error-log/sagas';
+import explorer from './explorer/sagas';
 import fileStorage from './fileStorage/sagas';
 import flashFirmware, { FirmwareSagaContext } from './firmware/sagas';
 import hub from './hub/sagas';
@@ -30,6 +31,7 @@ export default function* (): Generator {
         lwp3BootloaderProtocol(),
         editor(),
         errorLog(),
+        explorer(),
         flashFirmware(),
         hub(),
         licenses(),