diff --git a/tools/docker/Dockerfile b/tools/docker/Dockerfile
index e1d85d003..80b719ab1 100644
--- a/tools/docker/Dockerfile
+++ b/tools/docker/Dockerfile
@@ -3,7 +3,7 @@ FROM 32bit/ubuntu:16.04
 # Tools
 RUN apt-get update && \
   apt-get install -y --no-install-recommends \
-  build-essential doxygen git wget unzip python-serial \
+  build-essential doxygen git wget unzip python-serial python-pip \
   default-jdk ant srecord iputils-tracepath rlwrap \
   mosquitto mosquitto-clients \
   && apt-get clean
@@ -42,6 +42,12 @@ RUN wget https://developer.nordicsemi.com/nRF5_IoT_SDK/nRF5_IoT_SDK_v0.9.x/nrf5_
 
 ENV NRF52_SDK_ROOT /usr/nrf52-sdk
 
+# Install sphinx and sphinx_rtd_theme, required for building and testing the
+# readthedocs API documentation
+RUN pip install --upgrade pip
+RUN pip install setuptools
+RUN pip install sphinx_rtd_theme sphinx
+
 # Create user, enable X forwarding, add to group dialout
 # -e DISPLAY=$DISPLAY -v /tmp/.X11-unix:/tmp/.X11-unix
 RUN export uid=1000 gid=1000 && \