Significantly Improve the Performance of Microsoft Access Databases with Linked Tables
http://www.fmsinc.com/microsoftaccess/performance/linkeddatabase.html
A split database architecture is best for developing, maintaining, and deploying Microsoft Access applications. The front-end database contains the all the Access objects except the tables which reside in a separate back-end Access Jet database. The front-end database links to the tables in the back-end database, so it can be updated without worrying about changes to the data.