diff --git a/BUILD.md b/BUILD.md
index 7752241..c5c91d7 100644
--- a/BUILD.md
+++ b/BUILD.md
@@ -31,8 +31,6 @@ Create a .deb:
 
 ## macOS
 
-## macOS
-
 Install Xcode from the Mac App Store. Once it's installed, run it for the first time to set it up. Also, run this to make sure command line tools are installed: `xcode-select --install`. And finally, open Xcode, go to Preferences > Locations, and make sure under Command Line Tools you select an installed version from the dropdown. (This is required for installing Qt5.)
 
 Download and install Python 3.7.4 from https://www.python.org/downloads/release/python-374/. I downloaded `python-3.7.4-macosx10.9.pkg`.
@@ -70,4 +68,22 @@ And then run `build_app.py --with-codesign`:
 pipenv run ./install/macos/build_app.py --with-codesign
 ```
 
-The output is in the `dist` folder.
\ No newline at end of file
+The output is in the `dist` folder.
+
+## Windows
+
+Download Python 3.7.6, 32-bit (x86) from https://www.python.org/downloads/release/python-376/. I downloaded python-3.7.6.exe. When installing it, make sure to check the "Add Python 3.7 to PATH" checkbox on the first page of the installer.
+
+Open a command prompt and cd to the gpgsync folder. If you don't have it already, install pipenv (`pip install pipenv`). Then install dependencies:
+
+```
+python -m pipenv install --dev
+```
+
+Install the Qt 5.14.1 from https://www.qt.io/offline-installers. I downloaded qt-opensource-windows-x86-5.14.1.exe. In the installer, unfortunately you have login to an account. Then all you need `Qt` > `Qt 5.14.1` > `MSVC 2017 32-bit`.
+
+After that you can launch GPG Sync during development with:
+
+```
+python -m pipenv run python dev_scripts\dangerzone
+```
diff --git a/dangerzone/__init__.py b/dangerzone/__init__.py
index 72e6eff..83b4e95 100644
--- a/dangerzone/__init__.py
+++ b/dangerzone/__init__.py
@@ -8,7 +8,12 @@ import time
 
 from .common import Common
 from .main_window import MainWindow
-from .docker_installer import is_docker_installed, is_docker_ready, DockerInstaller
+from .docker_installer import (
+    is_docker_installed,
+    is_docker_ready,
+    launch_docker_windows,
+    DockerInstaller,
+)
 
 dangerzone_version = "0.1.0"
 
@@ -49,6 +54,30 @@ def main(filename):
 
         return
 
+    if platform.system() == "Windows":
+        if not is_docker_installed(common):
+            print("Docker is not installed")
+            docker_installer = DockerInstaller(common)
+            docker_installer.start()
+            # Quit after the installer runs, because it requires rebooting
+            return
+
+        if not is_docker_ready(common):
+            print("Docker is not running")
+            launch_docker_windows()
+
+            # Wait up to 20 minutes for docker to be ready
+            for i in range(120):
+                if is_docker_ready(common):
+                    main(filename)
+                    return
+
+                print("Waiting for docker to be available ...")
+                time.sleep(1)
+
+            # Give up
+            print("Docker not available, giving up")
+
     # Main window
     main_window = MainWindow(common)
 
diff --git a/dangerzone/common.py b/dangerzone/common.py
index 8a79777..95dc508 100644
--- a/dangerzone/common.py
+++ b/dangerzone/common.py
@@ -30,8 +30,14 @@ class Common(object):
 
         # Temporary directory to store pixel data
         # Note in macOS, temp dirs must be in /tmp (or a few other paths) for Docker to mount them
-        self.pixel_dir = tempfile.TemporaryDirectory(prefix="/tmp/dangerzone-pixel-")
-        self.safe_dir = tempfile.TemporaryDirectory(prefix="/tmp/dangerzone-safe-")
+        if platform.system() == "Windows":
+            self.pixel_dir = tempfile.TemporaryDirectory(prefix="dangerzone-pixel-")
+            self.safe_dir = tempfile.TemporaryDirectory(prefix="dangerzone-safe-")
+        else:
+            self.pixel_dir = tempfile.TemporaryDirectory(
+                prefix="/tmp/dangerzone-pixel-"
+            )
+            self.safe_dir = tempfile.TemporaryDirectory(prefix="/tmp/dangerzone-safe-")
         print(
             f"Temporary directories created, dangerous={self.pixel_dir.name}, safe={self.safe_dir.name}"
         )
@@ -51,6 +57,10 @@ class Common(object):
         # Container runtime
         if platform.system() == "Darwin":
             self.container_runtime = "/usr/local/bin/docker"
+        elif platform.system() == "Windows":
+            self.container_runtime = (
+                "C:\\Program Files\\Docker\\Docker\\resources\\bin\\docker.exe"
+            )
         else:
             self.container_runtime = "podman"
 
diff --git a/dangerzone/docker_installer.py b/dangerzone/docker_installer.py
index eb1a1ea..82db353 100644
--- a/dangerzone/docker_installer.py
+++ b/dangerzone/docker_installer.py
@@ -5,17 +5,23 @@ import tempfile
 import subprocess
 import shutil
 import time
+import platform
 from PyQt5 import QtCore, QtGui, QtWidgets
 
 
 def is_docker_installed(common):
-    # Does the docker binary exist?
-    if os.path.isdir("/Applications/Docker.app") and os.path.exists(
-        common.container_runtime
-    ):
-        # Is it executable?
-        st = os.stat(common.container_runtime)
-        return bool(st.st_mode & stat.S_IXOTH)
+    if platform.system() == "Darwin":
+        # Does the docker binary exist?
+        if os.path.isdir("/Applications/Docker.app") and os.path.exists(
+            common.container_runtime
+        ):
+            # Is it executable?
+            st = os.stat(common.container_runtime)
+            return bool(st.st_mode & stat.S_IXOTH)
+
+    if platform.system() == "Windows":
+        return os.path.exists(common.container_runtime)
+
     return False
 
 
@@ -28,6 +34,11 @@ def is_docker_ready(common):
         return False
 
 
+def launch_docker_windows():
+    docker_desktop_path = "C:\\Program Files\\Docker\\Docker\\Docker Desktop.exe"
+    subprocess.Popen([docker_desktop_path])
+
+
 class DockerInstaller(QtWidgets.QDialog):
     def __init__(self, common):
         super(DockerInstaller, self).__init__()
@@ -36,7 +47,11 @@ class DockerInstaller(QtWidgets.QDialog):
         self.setWindowTitle("dangerzone")
         self.setWindowIcon(QtGui.QIcon(self.common.get_resource_path("logo.png")))
 
-        label = QtWidgets.QLabel("Dangerzone for macOS requires Docker")
+        label = QtWidgets.QLabel()
+        if platform.system() == "Darwin":
+            label.setText("Dangerzone for macOS requires Docker")
+        elif platform.system() == "Windows":
+            label.setText("Dangerzone for Windows requires Docker")
         label.setStyleSheet("QLabel { font-weight: bold; }")
         label.setAlignment(QtCore.Qt.AlignCenter)
 
@@ -50,17 +65,21 @@ class DockerInstaller(QtWidgets.QDialog):
         self.install_button.setStyleSheet("QPushButton { font-weight: bold; }")
         self.install_button.clicked.connect(self.install_clicked)
         self.install_button.hide()
-        self.launch_button = QtWidgets.QPushButton("Launch Docker")
-        self.launch_button.setStyleSheet("QPushButton { font-weight: bold; }")
-        self.launch_button.clicked.connect(self.launch_clicked)
-        self.launch_button.hide()
+
+        if platform.system() == "Darwin":
+            self.launch_button = QtWidgets.QPushButton("Launch Docker")
+            self.launch_button.setStyleSheet("QPushButton { font-weight: bold; }")
+            self.launch_button.clicked.connect(self.launch_clicked)
+            self.launch_button.hide()
+
         self.cancel_button = QtWidgets.QPushButton("Cancel")
         self.cancel_button.clicked.connect(self.cancel_clicked)
 
         buttons_layout = QtWidgets.QHBoxLayout()
         buttons_layout.addStretch()
         buttons_layout.addWidget(self.install_button)
-        buttons_layout.addWidget(self.launch_button)
+        if platform.system() == "Darwin":
+            buttons_layout.addWidget(self.launch_button)
         buttons_layout.addWidget(self.cancel_button)
         buttons_layout.addStretch()
 
@@ -72,8 +91,14 @@ class DockerInstaller(QtWidgets.QDialog):
         layout.addStretch()
         self.setLayout(layout)
 
-        self.tmp_dir = tempfile.TemporaryDirectory(prefix="/tmp/dangerzone-docker-")
-        self.dmg_filename = os.path.join(self.tmp_dir.name, "Docker.dmg")
+        if platform.system == "Darwin":
+            self.tmp_dir = tempfile.TemporaryDirectory(prefix="/tmp/dangerzone-docker-")
+            self.installer_filename = os.path.join(self.tmp_dir.name, "Docker.dmg")
+        else:
+            self.tmp_dir = tempfile.TemporaryDirectory(prefix="dangerzone-docker-")
+            self.installer_filename = os.path.join(
+                self.tmp_dir.name, "Docker for Windows Installer.exe"
+            )
 
         # Threads
         self.download_t = None
@@ -105,19 +130,22 @@ class DockerInstaller(QtWidgets.QDialog):
         self.timer.start(10)
 
     def start_download(self):
-        self.download_t = Downloader(self.dmg_filename)
+        self.download_t = Downloader(self.installer_filename)
         self.download_t.download_finished.connect(self.download_finished)
         self.download_t.download_failed.connect(self.download_failed)
         self.download_t.update_progress.connect(self.update_progress)
         self.download_t.start()
 
     def install_finished(self):
-        self.task_label.setText("Finished installing Docker")
+        if platform.system() == "Darwin":
+            self.task_label.setText("Finished installing Docker")
+            self.launch_button.show()
+            self.cancel_button.setEnabled(True)
+        elif platform.system == "Windows":
+            self.task_label.setText("Reboot to finish installing Docker")
         self.install_t = None
         self.progress.hide()
         self.install_button.hide()
-        self.launch_button.show()
-        self.cancel_button.setEnabled(True)
 
     def install_failed(self, exception):
         print(f"Install failed: {exception}")
@@ -141,16 +169,17 @@ class DockerInstaller(QtWidgets.QDialog):
         self.timer.start(10)
 
     def start_installer(self):
-        self.install_t = Installer(self.dmg_filename)
+        self.install_t = Installer(self.installer_filename)
         self.install_t.install_finished.connect(self.install_finished)
         self.install_t.install_failed.connect(self.install_failed)
         self.install_t.update_task_label.connect(self.update_task_label)
         self.install_t.start()
 
     def launch_clicked(self):
-        print("Launching Docker")
-        self.accept()
-        subprocess.Popen(["open", "-a", "Docker.app"])
+        if system.platform() == "Darwin":
+            print("Launching Docker")
+            self.accept()
+            subprocess.Popen(["open", "-a", "Docker.app"])
 
     def cancel_clicked(self):
         self.reject()
@@ -175,22 +204,25 @@ class Downloader(QtCore.QThread):
     download_failed = QtCore.pyqtSignal(int)
     update_progress = QtCore.pyqtSignal(int, int)
 
-    def __init__(self, dmg_filename):
+    def __init__(self, installer_filename):
         super(Downloader, self).__init__()
-        self.dmg_filename = dmg_filename
+        self.installer_filename = installer_filename
+
+        if platform.system() == "Darwin":
+            self.installer_url = "https://download.docker.com/mac/stable/Docker.dmg"
+        elif platform.system() == "Windows":
+            self.installer_url = "https://download.docker.com/win/stable/Docker%20for%20Windows%20Installer.exe"
 
     def run(self):
-        print(f"Downloading docker to {self.dmg_filename}")
-        with requests.get(
-            "https://download.docker.com/mac/stable/Docker.dmg", stream=True
-        ) as r:
+        print(f"Downloading docker to {self.installer_filename}")
+        with requests.get(self.installer_url, stream=True) as r:
             if r.status_code != 200:
                 self.download_failed.emit(r.status_code)
                 return
             total_bytes = int(r.headers.get("content-length"))
             downloaded_bytes = 0
 
-            with open(self.dmg_filename, "wb") as f:
+            with open(self.installer_filename, "wb") as f:
                 for chunk in r.iter_content(chunk_size=8192):
                     if chunk:  # filter out keep-alive new chunks
                         downloaded_bytes += f.write(chunk)
@@ -205,34 +237,51 @@ class Installer(QtCore.QThread):
     install_failed = QtCore.pyqtSignal(str)
     update_task_label = QtCore.pyqtSignal(str)
 
-    def __init__(self, dmg_filename):
+    def __init__(self, installer_filename):
         super(Installer, self).__init__()
-        self.dmg_filename = dmg_filename
+        self.installer_filename = installer_filename
 
     def run(self):
         print(f"Installing Docker")
-        try:
-            # Mount the dmg
-            self.update_task_label.emit(f"Mounting Docker.dmg")
-            subprocess.run(["hdiutil", "attach", "-nobrowse", self.dmg_filename])
 
-            # Copy Docker.app to Applications
-            self.update_task_label.emit("Copying Docker into Applications")
-            shutil.copytree("/Volumes/Docker/Docker.app", "/Applications/Docker.app")
+        if platform.system() == "Darwin":
+            try:
+                # Mount the dmg
+                self.update_task_label.emit(f"Mounting Docker.dmg")
+                subprocess.run(
+                    ["hdiutil", "attach", "-nobrowse", self.installer_filename]
+                )
 
-            # Sync
-            self.update_task_label.emit("Syncing filesystem")
-            subprocess.run(["sync"])
+                # Copy Docker.app to Applications
+                self.update_task_label.emit("Copying Docker into Applications")
+                shutil.copytree(
+                    "/Volumes/Docker/Docker.app", "/Applications/Docker.app"
+                )
 
-            # Wait, to prevent early crash
-            time.sleep(1)
+                # Sync
+                self.update_task_label.emit("Syncing filesystem")
+                subprocess.run(["sync"])
 
-            # Unmount the dmg
-            self.update_task_label.emit(f"Unmounting /Volumes/Docker")
-            subprocess.run(["hdiutil", "detach", "/Volumes/Docker"])
+                # Wait, to prevent early crash
+                time.sleep(1)
 
-            self.install_finished.emit()
+                # Unmount the dmg
+                self.update_task_label.emit(f"Unmounting /Volumes/Docker")
+                subprocess.run(["hdiutil", "detach", "/Volumes/Docker"])
+
+                self.install_finished.emit()
+
+            except Exception as e:
+                self.install_failed.emit(str(e))
+                return
+
+        elif platform.system() == "Windows":
+            try:
+                # Run the installer
+                subprocess.run([self.installer_filename])
+                self.install_finished.emit()
+
+            except Exception as e:
+                self.install_failed.emit(str(e))
+                return
 
-        except Exception as e:
-            self.install_failed.emit(str(e))
-            return