In access 97 to 2003 you can put all of your user defined functions in a database .mdb or compile to .mde if you want to prevent any changes. Then change the file extension to .mda. In your working db you can open a vba window go to references where you can browse and select your .mda file. I think the same works with access 2010, but I'm guessing there might me a different file extension if the vba db is created in 2007/2010 format.