The performance of winter tires is characterized by snow traction and ice skid tests. Winter tire testing is reviewed in regards to the hardware used, design of a test program, site selection, and data analysis. The description of the hardware includes a review of a new traction measurement system. The system incorporates a traction truck with an instrumented axle at a driven wheel position interfaced with a mini-computer which controls the test, stores the measurements, and performs the data analysis.