diff --git a/.travis.sh b/.travis.sh
index 4b80d23a7..14eb9f455 100755
--- a/.travis.sh
+++ b/.travis.sh
@@ -23,6 +23,7 @@ function build_and_test ()
   fi
 
   cmake $SOURCE_DIR \
+      -DCMAKE_BUILD_TYPE=Debug \
       -DGTSAM_BUILD_TESTS=$GTSAM_BUILD_TESTS \
       -DGTSAM_BUILD_UNSTABLE=$GTSAM_BUILD_UNSTABLE \
       -DGTSAM_BUILD_EXAMPLES_ALWAYS=$GTSAM_BUILD_EXAMPLES_ALWAYS \