Joseph Wresinski, founder of the International Movement ATD Fourth World, distinguishing "lack of basic security" (poverty) and "chronic poverty" (extreme poverty), linking the eradication of extreme poverty by allowing people currently experiencing it a real opportunity to exercise all their human rights:
"The lack of basic security connotes the absence of one or more factors enabling individuals and families to assume basic responsibilities and to enjoy fundamental rights. The situation may become widespread and result in more serious and permanent consequences. The lack of basic security leads to chronic poverty when it simultaneously affects several aspects of people’s lives, when it is prolonged and when it severely compromises people’s chances of regaining their rights and of reassuming their responsibilities in the foreseeable future. "This definition was mentioned previously, in June 1989, in the preliminary report on the realization of economic, social and cultural rights by the UN Special Rapporteur Danilo Türk. It is still in use today, among others, in the current UN Guiding Principles on Extreme Poverty and Human Rights adopted by the UN Human Rights Council in September 2012

Consumption-based definition
Extreme poverty is defined by the international community as living below $1.90 a day, as measured in 2011 international prices (equivalent to $2.12 in 2018). This number, also known as the international poverty line, is periodically updated to account for inflation and differences in the cost of living; it was originally defined at $1.00 a day in 1996.
This prompted the organization of a 2nd UN LDC conference almost a decade later. The second UN LDC Conference was held between 3 and 14 September 1990, once again in Paris, the second UN LDC Conference was convened to measure the progress made by the LDCs towards fulfilling their development goals during the 1980s. Recognizing the problems that plagued the LDCs over the past decade, the conference formulated a new set of national and international policies to accelerate the growth rates of the poorest nations. These new principles were embodied in the "Paris Declaration and Programme of Action for the Least Developed Countries for the 1990s".The fourth UN LDC Conference was the most recent conference. It was held in May 2011 in Istanbul, recognized that the nature of development had fundamentally changed since the 1st conference held almost 30 years earlier. In the 21st century, the capital flow into emerging economies has increasingly become dominated by foreign direct investment and remittances, as opposed to bilateral and multilateral assistance. Moreover, since the 1980s, significant structural changes have taken place on the international stage. With the creation of the G-20 conference of the largest economic powers, including many nations in the Global South, formerly undeveloped nations are now able to have a much larger say in international relations. Furthermore, the conference recognized that in the midst of a deep global recession, coupled with multiple crises (energy, climate, food, etc. ), the international community would have fewer resources to aid the LDCs.