This paper explores the nature of vulnerability and its relationship to chronic poverty in rural Bangladesh drawing from 293 life-history interviews conducted by the author and a small team of researchers in rural Bangladesh in 2007. The aim of the paper is to provide insights into causal processes, within contextual detail, in order to complement quantitative research into patterns of vulnerability and to inform social protection policy. The paper explores vulnerability as a key aspect of poverty and takes a longitudinal and multidimensional perspective. The paper focuses on causes of long-term wellbeing decline in poor people’s lives, explored as the combination of: a lack of opportunities, or impeded ability to exploit opportunities; exposure to acute ‘shocks’ and chronic downward pressures; and the long-term diminution of coping resources. It considers how short-term coping with shocks and downward pressures can sometimes affect prospects for long-term improvement, including the danger that poverty traps may be deepened by destructive coping strategies. It also discusses how perceived future threats to life and livelihood can have present consequences, again particularly for the poorest, who tend to be most exposed to key causes of decline and least protected when they happen. The paper provides evidence that poverty traps are linked to vulnerability. It argues that this linkage occurs not only because of the denuded endowments of key assets and capabilities of vulnerable people, but also because of liabilities and disabilities. Increased exposure to the most damaging forms of shocks and downward pressures, and impeded or damaging coping strategies result. These all combine to contribute to patterns of cumulative decline for the most vulnerable.