Sage MAS 90 is a LAN-based system that operates on Windows servers. Sage MAS 200 offers client-server solutions that run on the Windows and SQL Server environments. Thin-client architecture in Sage MAS 200 delivers excellent performance for customers with multiple locations and personnel who work in the field. A straightforward upgrade path from Sage MAS 90 to Sage MAS 200 allows customers to consistently retain the same flexible, stable and reliable functionality as their businesses evolve—eliminating the need to re-train or convert data.