Exposure to asymmetrical risk forces the poor into a precarious existence, leaving them permanently vulnerable to a variety of shocks which limit their capacity to save, constrain their livelihood options and bind them in a state of poverty or near poverty. This level of poverty is not measured by their location slightly above or below an arbitrarily constructed subsistence line, but by their degrees of vulnerability to a variety of risks originating in a market driven economic system. As a result, households may periodically move above the poverty line but could easily regress below it in the face of shocks. This paper sets out to explore the sources of asymmetrical risk, which leave some people more vulnerable than others, and to relate these asymmetries to the structurally derived variations in their socio-economic circumstances. Vulnerability that originates in ethnicity, gender and climate is also an important factor in exposure to asymmetrical risk. This paper limits its focus to a discussion of vulnerabilities originating in the inequitable economic opportunity structures, which circumscribe the lives of the poor. The paper initially examines the nature of such vulnerabilities and how this may serve to trap particular segments of the population in conditions of insecurity and poverty. It then goes on to relate these to the unjust socio-economic circumstances which create and perpetuate them.