The 1993 Geospace Environment Modeling (GEM) workshops, sponsored by the National Science Foundation, will be held in Snowmass, Colo., from June 28 to July 2. As with last year's meeting, there will be two workshops: the Boundary Layer Campaign from June 28–30 and the Magnetotail/Substorm Campaign from July 1–2. At the workshop on the Boundary Layer Campaign (conveners: L. Lyons, Aerospace Corp.; T. Rosenberg, University of Maryland; C. Russell, University of California at Los Angeles), plenary sessions will include a few invited talks and tutorials on selected topics in geospace environment modeling and observing. Contributed posters on any aspects of dayside boundary layer and cusp physics, magnetosheath modeling, and ionospheric signatures of the boundary layer and cusp are solicited. Open working groups will meet to evaluate progress, strategies, and opportunities in observing and modeling the dayside boundary layer and cusp region.