The Johnson Space Center Director's Discretionary Fund Program Annual Report provides a brief review of the status of projects undertaken during the 1990 fiscal year. Three space exploration initiative related issues were focused on: regenerative life support, human spacecraft design, and lunar surface habitat. A viable program of life sciences, space sciences, and engineering research has been maintained. Johnson Space Center AERODYNAMICS; AEROSPACE ENGINEERING; HABITATS; LIFE SCIENCES; LIFE SUPPORT SYSTEMS; LUNAR SURFACE; RESEARCH FACILITIES; SPACE EXPLORATION; SPACECRAFT DESIGN; ANTENNAS; COMBUSTION; COMPUTER PROGRAMS; COSMIC DUST; HIGH TEMPERATURE SUPERCONDUCTORS; HOLOGRAPHY; LONG DURATION EXPOSURE FACILITY; SOIL SCIENCE; SPACE SHUTTLES; TEMPERATURE MEASUREMENT...