diff --git a/Dockerfile b/Dockerfile
index 02c07f40a..b11baa12c 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -12,4 +12,5 @@ RUN \
   virtualenv --no-site-packages -p python2 venv && \
   ./venv/bin/python setup.py install
 
+ENV DOCKER_RUN True
 ENTRYPOINT [ "./venv/bin/letsencrypt", "--text" ]
diff --git a/letsencrypt/client/client.py b/letsencrypt/client/client.py
index d415403f3..3a4388076 100644
--- a/letsencrypt/client/client.py
+++ b/letsencrypt/client/client.py
@@ -336,7 +336,8 @@ def init_csr(privkey, names, cert_dir):
     csr_pem, csr_der = crypto_util.make_csr(privkey.pem, names)
 
     # Save CSR
-    le_util.make_or_verify_dir(cert_dir, 0o755)
+    if not os.environ.get('DOCKER_RUN'):
+	le_util.make_or_verify_dir(cert_dir, 0o755)
     csr_f, csr_filename = le_util.unique_file(
         os.path.join(cert_dir, "csr-letsencrypt.pem"), 0o644)
     csr_f.write(csr_pem)