The basic nees approach in development discourse focuses on the measurement of poverty with a view to its elimination in the shortest amount of time. As one of the major approaches to the measurement of poverty, this approach attempts to define the absolute minimum necessary for long term physical well-being, usually in terms of consumption goods; the poverty line is then defined as the amount of income required to satisfy those needs. Related approaches, taking their cue from the work of Amartya Sen, focus on 'capabilities' rather than consumption. As a result, it is typically the case that emphasis is placed only on the minimum level of consumption of 'basic needs' such as food, water, shelter, sanitation, healthcare, and education, although the basic needs approach used by Sarlo, for Canada, has an expanded list of necessities, as listed in the accompanying chart. Development programs following the basic needs approach do not invest in economically productive activities that will help a society carry its own weight in the future, rather it focuses on allowing the society to consume just enough to rise above the poverty line and meet its basic needs. These programs focus more on subsistence than fairness. Nevertheless, in terms of "measurement", the basic needs or absolute approach does appear to be of great interest. The 1995 world summit on social development in Copenhagen had, as one of its principal declarations that all nations of the world should develop measures of both absolute and relative poverty and should gear national policies to "eradicate absolute poverty by a target date specified by each country in its national context."