International attention is focused more sharply on poverty reduction than for 20 years. The international target proposed by the Development Assistance Committee of the OECD has been widely adopted, namely to reduce by half by 2015 the proportion of people living in extreme poverty. But quite what this target might mean is obscured by the bewildering ambiguity with which the term ‘poverty’ is used, and by the many different indicators proposed to monitor poverty. Income poverty or human development? Sustainable livelihood or social inclusion? Current
consumption or future security? Different concepts imply different interventions.

The concepts have developed rapidly over the last three decades. There are nine fault-lines in the current debate, for example on the importance of monetary variables, on objective or subjective measures, and on the link between material income and
wider ‘functioning’ in society. Most agree that money income (or consumption) on its own is an imperfect measure of welfare, and also recognise the need to take account of variability over time. The idea of relative deprivation is widely accepted – at least in theory. There are different views, however, about the relative importance of non-monetary variables, like self-esteem, and about the weight that should be given to the views expressed by poor people themselves.
The conceptual debate is carried over to measurement. A small, craft industry has developed, especially at the international level, in measuring poverty and deprivation, often in response to the need to define targets at international conferences and
measure progress against them. Different models of poverty imply different indicators. Advocates of the participatory paradigm, in particular, are wary of quantification
and standardisation.