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An essential aspect of traffic safety is the skid resistance of asphalt wearing courses.Even if the traffic participant does not perceive directly the significance of skid resistance,the skid resistance is,amongst wearing course characteristics,nonetheless of primary importance for him.Acceptance and warranty requirements for skid resistance have been laid down in Germany in the technical guidelines a sa part of the contract since 2001.The skid resistance is measured by a side force machine SKM (modified SCRIM) 4 to 8 weeks after handing off for traffic and at the end of a four years warranty period.The required values vary dependent on the measuring speed,which is laid down as 80,60 or 40 km/h.At this time the background of experience for the manufacture of skid resistant surfaces is limited mainly to wearing courses made from asphalt concrete.As the skid resistance is substantially influenced by the surface texture,it was feared that it will not be possible to adhere to the requirements for wearing courses with a high chipping and low mortar content as for example stone mastic asphalt.The known prediction tests were either not perfected yet or not sufficiently correlated with the skid resistance measuring procedure when the skid resistance requirement was introduced.For this reason skid resistance measurements have been carried out on various wearing course types over a long period of time at various distances using the SKM.The paper shows the development of skid resistance over a longer period of time and gives information about the correlations between prognosis procedures and measured skid resistances.