Reviews : Planning for Earthquakes: Risk, Politics and Policy Philip R. Berke and Timothy Beatley Johns Hopkins University Press, Baltimore, Maryland, 1992. 210 pages. $38.00 (HB) Sharing Environmental Risks: How to Control Governments' Losses in Natural Disasters Raymond J. Burby, Beverly A. Cigler, Steven P. French, Edward J. Kaiser, Jack Kartez, Dale Roenigk, Dana Weist, and Dale Whittington. Westview Press, Inc., Boulder, Colorado, 1991. 280 pages. $57.50 (PB) Emergency Management: Principles and Practice for Local Government Thomas Drabek and Gerard J. Hoetmer, eds. International City Management Association, Washington, D.C. 1991. 368 pages. $35.95 (HB) ■ RISKY BUSINESS: NATURAL HAZARDS AND THE FIELD OF PLANNING