Grodziskie Przewozy Autobusowe (GPA) is a regional public bus transport provider based in Grodzisk Mazowiecki, Poland. Established as a project involving several local governments, it has grown into a network of more than 115 routes operated by over 167 buses, serving hundreds of thousands of passengers each month. GPA connects communities across the area and adjusts routes and timetables in response to local needs, roadworks and other changes, including arrangements to maintain transport for students.

The organisation provides practical information and tools to help passengers plan and manage their journeys. Its services include route timetables, maps and network diagrams, journey searches, bus location information and details on fares and monthly tickets. Passengers can also check when a bus is expected to arrive, review regulations and find information about ticket recognition and services beyond the GPA network. GPA additionally promotes trips to Kampinos National Park, with reservations available for transporting bicycles. Through service updates and passenger resources, the organisation supports everyday travel as well as selected leisure journeys.