The dimensioning of building services by the planner requires reliable data describing the meteorological conditiions at the site. This guideline supplies long-term meteorological data for 20 stations distributed fairly evenly over longitude and latitude. Where available, temperature, water vapour content, wind, cloud cover, duration of sunshine and solar irradiation are given. The guideline uses the systematic approach known in Germany from DIN 4710. The data are supplied as tables on CD ROM for use in simulation software and the like. VDI in indebted to the DWD for supplying the data, which have undergone extensive interpretation for use in the guideline.