||This report first gives a brief description of GSM mobile telephone systems and base stations, emphasizing some properties of these systems that may have an influence on the outcome of measurement activities. The rationale, design and reporting of measurements are then discussed. The existence and variations in different regulations, standards and recommendations are described, followed by an evaluation of measurement data in terms of science-based standards. The report ends with some conclusions and recommendations for further activities. Closer descriptions of the situation in some of the participating countries (Austria, Germany, France, Hungary and Sweden) are found in the Appendices.