diff --git a/BUILDING.md b/BUILDING.md
index 80e4fe0fa..cc1b63db0 100644
--- a/BUILDING.md
+++ b/BUILDING.md
@@ -22,6 +22,9 @@ You can also find the v142 toolset by searching through the individual component
 While you're there, you can also install Python 3 and Git if needed.
 
 1. Clone the Ship of Harkinian repository
+
+_Note: Be sure to either clone with the ``--recursive`` flag or do ``git submodule init`` after cloning to pull in the libultraship submodule!_
+
 2. Place one or more [compatible](#compatible-roms) roms in the `OTRExporter` directory with namings of your choice
 
 _Note: Instructions assume using powershell_