diff --git a/contrib/taler-terms-generator.in b/contrib/taler-terms-generator.in
index 6b4664137..1bf030c16 100755
--- a/contrib/taler-terms-generator.in
+++ b/contrib/taler-terms-generator.in
@@ -143,6 +143,12 @@ while getopts ':a:C:hi:l:o:p:t:' OPTION; do
     esac
 done
 
+if ! which sphinx-build > /dev/null
+then
+    echo "Command 'sphinx-build' not found, but required. Please install sphinx."
+    exit 1
+fi
+
 BUILDDIR=$(mktemp -d /tmp/taler-terms-XXXXXX)
 if [ ! -f "${VERSION}.rst" ]
 then
diff --git a/debian/control b/debian/control
index 995b5d3ee..11a4a73ef 100644
--- a/debian/control
+++ b/debian/control
@@ -39,6 +39,9 @@ Depends:
  netbase,
  ${misc:Depends},
  ${shlibs:Depends}
+Recommends:
+ python3-sphinx,
+ python3-sphinx-rtd-theme
 Description: Libraries to talk to a GNU Taler exchange.
   The package also contains various files fundamental
   to all GNU Taler installations, such as the