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While ecological resilience may explain why apparent symptoms of desertification are often temporary, social resilience can prevent degradation resulting from overexploitation of land in response to drought and other constraints. This paper describes a Social Resilience Model in which actors switch from performance strategies to survival strategies when the perceived severity of constraints exceeds a critical performance-survival threshold (PST). This is determined in comparison with a reference mode that depends on a learning facility developed by repeated exposure to cycles of constraint, search and feedback. Actors select particular strategies by comparing welfare gains with their aspiration levels-a concept that allows more flexible decision making than profit maximizing or satisficing alone. The model is tested in the silvopastoral zone of Senegal, where desertification is not as widespread as commonly assumed, despite severe constraints. The two major ethnic groups, the Wolof (mainly croppers) and the Peul (mainly pastoralists) anticipate and respond to environmental and socio-economic constraints differently, and have different performance and survival strategies. The Peul have the higher social resilience, with more flexible decision-making objectives, greater mobility, a more extensive action space, a learning facility supporting efficient search and feedback processes, a reference mode attuned to high anticipation and recognition of stress, and a high PST. They also exhibit more continuous performance-survival switching than the Wolof, who make a radical change from cropping to labour migration and reliance on external support. Copyright (C) 2004 John Wiley Sons, Ltd.