diff --git a/README.md b/README.md
index 146ed967..c632e282 100644
--- a/README.md
+++ b/README.md
@@ -150,5 +150,7 @@ $ docker run -d \
 
 * `NGINX_PROXY_CONTAINER`- If for some reason you can't use the docker --volumes-from option, you can specify the name or id of the nginx-proxy container with this variable.
 
+* `NGINX_DOCKER_GEN_LINKED_CONTAINER_ENVVAR` - If you are running nginx-gen as a [linked container](https://docs.docker.com/engine/userguide/networking/default_network/dockerlinks/) and its ID cannot be predetermined, specify the name of the environment variable of the form `<alias>_NAME` that gets set by Docker when linking containers.
+
 #### Examples:
 If you want other examples how to use this container, look at [docker-letsencrypt-nginx-proxy-companion-examples] (https://github.com/fatk/docker-letsencrypt-nginx-proxy-companion-examples).
diff --git a/app/entrypoint.sh b/app/entrypoint.sh
index 3b3232ab..7e3bbda0 100755
--- a/app/entrypoint.sh
+++ b/app/entrypoint.sh
@@ -75,7 +75,16 @@ source /app/functions.sh
 if [[ "$*" == "/bin/bash /app/start.sh" ]]; then
     check_docker_socket
     if [[ -z "${NGINX_DOCKER_GEN_CONTAINER:-}" ]]; then
-        [[ -z "${NGINX_PROXY_CONTAINER:-}" ]] && get_nginx_proxy_cid
+        if [[ ! -z "${NGINX_DOCKER_GEN_LINKED_CONTAINER_ENVVAR:-}" ]]; then
+            # `NGINX_DOCKER_GEN_LINKED_CONTAINER_ENVVAR` is expected to
+            # contain the name of the environment variable of the form
+            # `<alias>_NAME` that gets set by Docker when linking containers.
+            # We need to chop off the `/` prefix to be able to use its
+            # value in Docker Remote API calls.
+            export NGINX_DOCKER_GEN_CONTAINER=$(echo ${!NGINX_DOCKER_GEN_LINKED_CONTAINER_ENVVAR} | sed 's/^\///')
+        else
+            [[ -z "${NGINX_PROXY_CONTAINER:-}" ]] && get_nginx_proxy_cid
+        fi
     fi
     check_writable_directory '/etc/nginx/certs'
     check_writable_directory '/etc/nginx/vhost.d'