This thesis is comprised of three distinct chapters, each of which is concerned insome way with the measurement of poverty.The
first chapter provides social preference conditions which are both necessary and sufficient for a poverty line to arise endogenously. In so doing, it turns out that the apparently independent identi
fication and aggregation problems in poverty measurement are subtly intertwined. Necessary and sufficient conditions are provided for the existence of both relative and absolute poverty lines. In each case, one of the conditions is a familiar weak monotonicity property. The other conditions are simple consistency requirements.In the second chapter, we propose classes of intertemporal poverty measures which take into account both the debilitating impact of prolonged spells in poverty and the mitigating effect of periods of affluence on subsequent poverty. The weight assigned to the level of poverty in each time period depends on the length of the preceding spell of poverty or of non-poverty. The proposed classes of intertemporal poverty measures are quite general and allow for a range of possible judgements as to the overall impact on a poor period of preceding spells of poverty or affluence. We discuss the properties of the proposed classes of measures and axiomatically characterize them.The third chapter is an empirical application of the intertemporal poverty measures proposed in the second chapter. The new measures, together with an existing intertemporal poverty measure from the literature, are used to analyse intertemporal poverty in Great Britain during the period 1991-2005, using data from the British Household Panel Survey. Previous studies on poverty using this data-set have employed static measures of poverty. We illustrate how the use of intertemporal poverty measures makes it possible to analyse aspects of poverty which cannot be captured by static, annual, measures of poverty. We then model the determinants of intertemporal poverty, conditional upon being poor, using a Heckman two-step selection model.