Abstract: For monitoring railway tracks on a frequent basis, instrumentation packages are installed in service vehicles (18), for example in passenger carriages. The instrumentation package (16) comprises sensors (35, 36, 42) mounted on a bogie (24) of the vehicle (18), which provide data to a computer (40). The computer (40) processes the data to characterise the track quality, and stores the results tagged with positional information. At intervals these stored results are automatically transferred by radio to a remote base station (12). An operator at the base station can monitor the track quality daily, and hence advise on cost-effective maintenance schedules.