This paper discusses some of the important details of tire tread design, and presents some test results showing how tread design parameters can delay the build-up of hydrodynamic pressure in the tire footprint area and improve braking and cornering traction on wet or flooded pavement surfaces. It is also shown how even minor differences in pavement texture can be of extreme importance in providing good traction under wet conditions, and a proposed technique for measuring surface roughness and predicting the wet friction level of a given pavement texture is discussed. The paper concludes with a brief summary of current research on tire hydroplaning.