After lagging for decades, solar power is booming; its growth rate of 16 percent per year from 1990-1997 ranks it as the world's second fastest-growing energy source after wind power. Worldwatch Institute attributes the boom to declining manufacturing costs and subsidies. Japan, Europe and the United States, for example, have instituted programs to encourage use of solar energy. The Worldwatch report appears in the September/October edition of Worldwatch Magazine, on the Web at www.worldwatch.org. The Worldwatch Institute can be reached at 1776 Massachusetts Ave. NW, Washington, DC 20036-1404 (202/452-1999).