INTRODUCTION The purpose of this report is to document the methodologies used in generating an emission inventory and an aerometric data bank for Houston@ Texas. The report also contains a detailed description of the emission inventory and a compilation of the aerometric data reported at the air monitoring station@ Mae Drive@ during the periods May - September of 1973 and 1974. This data base had been used extensively during the development of a probabilistic model relating atmospheric oxidant to its precursors@ taking into consideration the effects of meteorology@ atmospheric transformation and other relevant variables. This model development had been supported by the American Petroleum Institute through API Project EF-l9 and described in Ref. 1@ which is a companion document to this one. This report contains the data used in that project.