There are more people being affected by environmental change than ever before. The deterioration of the earth's physical condition appears to be accelerating. This sixth in a series of annual reports is a collection of 10 essays detailing the major threats to global environmental security and possible responses to them. Included are: (1) "A World at Risk" (Lester R. Brown, Christopher Flavin, and Sandra Postel); (2) "Halting Land Degradation" (Sandra Postel); (3) "Reexamining the World Food Prospect" (Lester R. Brown); (4) "Abandoning Homelands" (Jodi L. Jacobson); (5) "Protecting the Ozone Layer" (Cynthia Pollock Shea); (6) "Rethinking Transportation" (Michael Renner); (7) "Responding to AIDS" (Lori Heise); (8) "Enhancing Global Security" (Michael Renner); (9) "Mobilizing at the Grassroots" (Alan B. Durning); and (10) "Outlining a Global Action Plan" (Lester R. Brown, Christopher Flavin, and Sandra Postel). The report concludes with a statement of the belief that the 1990s needs to be a turn-around decade. (CW)