Those seeking a livelihood in marginal situations live ‘near the edge’ – outside developed nations there are few safety nets, so a failed harvest will probably not be cushioned by aid or government offers of alternatives. Environmental managers in a number of countries must cope with the problem of population movement into and population growth within marginal and vulnerable areas, and with increasing social differentiation, i.e. a widening gap between rich and poor (Glantz, 1994). Diverse factors cause marginalisation and social differentiation: economic development, innovations like new seeds, land speculation, eviction from conservation areas or enclosed land and many other causes. Marginalised people often cause worsening environmental damage as they struggle to survive, so environmental management frequently must deal with helping the poor toward sustainable livelihoods and away from causing and being victims of environmental degradation.