The "1990 Summer Study on High Energy Physics Research Directions for the Decade" was held in Snowmass, Colorado; June 25 - July 13, 1990. The Division of Particles and Fields of the American Physical Society organized the study and about 520 participants attended. This action will provide funds for publication of the proceedings and post conferences expenses. This study followed four highly successful summer studies held at Snowmass, Colorado, in 1982, 1984, 1986 and 1988. The 1990 summer study included physics at existing and anticipated hadron-hadron, e+e- and ep colliders; physics at fixed target energies; the physics potential of possible new facilities, such as B factories; non accelerator based physics; accelerator and detector initiatives; and the physics and technical ingredients of the initial SSC experimental program.
