This study explored the inservice training needs of teachers (in Taiwan) working with mentally handicapped students. Elementary (N=224) and junior high (N=171) school teachers of the retarded were surveyed concerning perceived competency levels and preferred inservice training topics and formats. Findings included: (1) both teacher groups selected the same 10 basic competencies as most important; (2) 8 of the 10 lowest rated competencies were also shared between groups; (3) both groups of teachers felt most competent in the area of guidance and least competent in the areas of "general competencies" and curriculum/instruction; (4) both groups showed consistency in their self assessments; (5) teacher sex and age were not related to competency levels; (6) teachers with junior teachers college training assessed their competencies higher than did teachers with standard college background in the area of curriculum and instruction; (7) teachers with the most experience teaching the retarded rated their competencies the highest; (8) formal inservice education formats were rated as most desirable by both groups; and (9) most desired inservice training activities were visiting other educational programs, a combination of program visitation and recreation, and workshops on instructional materials. Includes 21 references. (DB)