diff --git a/doc/install/install.rst b/doc/install/install.rst
index 35a38da27b..e7ff45b4fe 100644
--- a/doc/install/install.rst
+++ b/doc/install/install.rst
@@ -60,6 +60,9 @@ To install the required dependencies, you can use:
 
      sudo apt-get install cmake make gcc g++ flex bison libpcap-dev libssl-dev python-dev swig zlib1g-dev
 
+  In order to build Bro on Debian 9, install ``libssl1.0-dev`` instead
+  of ``libssl-dev``.
+
 * FreeBSD:
 
   Most required dependencies should come with a minimal FreeBSD install