A description is given of the structure and operation of 29 intermediate administrative units which provide consulting, advisory, administrative, or statistical services to local school districts in Pennsylvania. The basic services rendered by the units are in the areas of: (1) curriculum development and instructional improvement; (2) management; (3) continuing professional education; (4) pupil personnel; (5) instructional materials; (6) state and federal agency liaison; (7) educational planning; (8) special education; and (9) non-public services. (JD)