A procedure was developed to systematically reduce 199 indicators of teaching effectiveness identified in related literature to a more manageable number for use in the University of Washington's assessment system for student teachers. The Teaching Performance Assessment Instrument from the University of Georgia was used as a model for grouping the indicators. A variety of teacher education documents containing generic standards were then reviewed to insure that all important aspects of teaching effectiveness were included. Criteria for selection included: (1) whether the indicator addressed one or more than one behavior; (2) whether the indicator contained language which was overly specific and limited in its application; and (3) whether the indicator appeared more than once. This analysis resulted in 47 indicators of teaching effectiveness grouped into 3 major categories: planning, instruction, and professional responsibilities. Validation of the assessment system involved sending copies of the instruments to 631 selected authorities in the field. A copy of the materials sent to the validators is appended as well as a descriptive brochure of the system. (Author/JD)