The Association of Science-Technology Centers (ASTC) will develop an unusual "hands-on" training program in exhibit development for science museum staff. This four year program will strengthen the exhibition capabilities of small and medium-sized science museums throughout the US through a series of workshops and intensive cooperation between ASTC staff, "teaching museums," design consultants, and four "learner museums" that will lead to the creation of four finished exhibitions. Training will be managed by ASTC's existing Traveling Exhibits Service staff, assisted by a Project Advisory Committee and several nationally recognized exhibition consultants. The project will result in four l,000 square foot traveling exhibits that will reach more than 2,000,000 visitors at more than 30 museums, four permanent exhibits at the learner museums, and professional training and consultation in exhibit development for more than 30 museums staff, including long term training of staff from the four learner museums. NSF support will be augmented by $200,000 contributed by the learner museums.