Rationale, application for training, and implications for practice are presented for a school psychology training approach that is part of a broader Transactional-Ecological Psychology (TEP) Training Program. The TEP provides an innovative and unified approach to training in the areas traditionally called clinical, community, counseling and school psychology. Transactionalism is very broadly thought of as a system of inquiry in which behavior is considered to be a process between the "environed organism" and the constantly changing properties of natural settings. The TEP effort represents an attempt to develop competencies of scientific inquiry and other applications of transactional concepts. Competency areas are described at a level intended to be specific enough to have clear meaning, but not so detailed as to be unnecessarily inflexible or unwieldy in application. In addition, students are expected to have a solid understanding of fundamental psychology including history of the field, child development, personality and learning theory, social psychology and statistical procedures. The issues and problems of competency-based training and certification will be discussed. (Author)