I'm new to Access, and I've been working on a way to store large amounts of water quality data for the university research group I'm working for. I've designed a simple database (see attached screenshot) but my problem is how to make it easy for users to enter data. Specifically, I want the user to enter the trip information from one form, including which sites were visited. The form currently works fine, but it's not user-friendly. I want the user to select the sites using the SiteName from a combobox in the subdatasheet. I just can't figure out how to do it.