diff --git a/Makefile b/Makefile
index 21cd43348cb545bfbf0acd8985dd0e3a459ca8f1..4be361a56cb09fa5359d5ef03ccff3064b2e4e3d 100644
--- a/Makefile
+++ b/Makefile
@@ -79,7 +79,7 @@ conan: conan-install conan-create
 .PHONY: conan
 
 doc:
-	mkdir -p build && cd build && conan install .. -s $(CONAN_SETTINGS) \
+	mkdir -p build && cd build && conan install .. --build=missing -s $(CONAN_SETTINGS) \
 	  && cmake .. && cmake --build . --target doc-sphinx \
 	  && echo "The documentation starts at build/doc/sphinx_out/index.html ."
 .PHONY: doc