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The widespread drought of the early 1990s resulted in considerable stock losses in the semi?arid savanna of KwaZulu?Natal. We compared the influence of four drought response strategies on herd number, milk yield, cost and net present value for a communal cattle herd over the period 1983 to 2001 using a simulation modelling approach. The strategies were (1) no reaction to drought; (2) moving stock to areas not affected by drought; (3) purchasing replacement stock after the drought; and (4) supplementing stock during the drought with sugar?cane residues. Moving, buying or feeding stock generated greater milk yields and net benefits relative to no drought response, but at considerably greater cost. Cost:benefit was greatest where a small proportion of female stock (10 percent) were moved. By doing nothing in the face of regional drought, communal graziers may be acting rationally, given the constraints under which they operate. The study reveals that simulation modelling may provide a useful basis from which to assess the outcome of various management strategies for communal graziers, and for integrating the disparate suite of influences which drive decision?making on communal lands.