This document is the pilot study working towards a standardization of Gaussian plume models for specific air quality management applications. It summarizes the essential elements required of a Gaussian Plume model, compares the models participating in the Practical Demonstration, and compiles and evaluates the results of this model. It contains the full length papers prepared for the Practical Demonstration. These discuss: The 'Common Data Base' used for the Test City, brief descriptions of the models used in the Practical Demonstration, and the results of the model calculations for the Test City. Contains bibliography, list of participants in the Practical Demonstration, and list of panel members with their addresses, and a list of all NATO/CCMS Documents on the First Air Pollution Pilot Study.