diff --git a/README.md b/README.md
new file mode 100644
index 0000000..92af485
--- /dev/null
+++ b/README.md
@@ -0,0 +1,31 @@
+# Git authentication tools for Google Compute Engine
+
+The `git-cookie-authdaemon` uses the GCE metadata server to acquire an
+OAuth2 access token and configures `git` to always present this OAuth2
+token when connecting to googlesource.com or
+[Google Cloud Source Repositories][CSR].
+
+[CSR]: https://cloud.google.com/source-repositories/
+
+## Setup
+
+Launch the GCE VMs with the gerritcodereview scope requested, for example:
+
+```
+gcloud compute instances create \
+  --scopes https://www.googleapis.com/auth/gerritcodereview \
+  ...
+```
+
+## Installation
+
+Install the daemon within the VM image and start it running:
+
+```
+sudo apt-get install git
+git clone https://gerrit.googlesource.com/gcompute-tools/
+./gcompute-tools/git-cookie-authdaemon
+```
+
+The daemon launches itself into the background and continues
+to keep the OAuth2 access token fresh.