The perceptions of preservice student teachers as to the effectiveness of cooperating teachers' behaviors were used in this study to determine the competencies required in a cooperating teacher for each curricular group. During the terminal two weeks of student teaching, three groups of student teachers, one each in elementary education, physical education, and secondary social studies, were asked to identify effective cooperating teacher behaviors and to rate them on a need scale. Those behaviors rated "definitely needed" by a majority of the students were determined to be competency requirements for that group. All groups considered the cooperating teachers'"development of student teachers perception of the teaching-learning process" as the most important major category of behavior. Twenty-seven competencies divided into three large categories (perceptions of the teaching-learning process, understanding pupils, developing behaviors of a professional) were constructed from the student teacher responses. Agreement was noted at the level of major categories and subcategories, but a lack of agreement as to particular competencies emphasized the need for investigations in the various curricular areas to develop more curricular-specific competencies. (MB)