The states parties meet every five years at a Review Conference (or RevCon) to assess the implementation of the treaty. There is a Preparatory Committee (or PrepCom) conference that meets for two weeks in the three years leading up to the Review Conference. In preparation for the 2015 Review Conference, there are three PrepComs: in 2012 (Vienna), 2013 (Geneva), and 2014 (New York). The Review Conferences always take place in New York.

During the PrepComs, many working papers are tabled, and the Chairman drafts a Final Summary statement, but none of these documents are binding. Rather, these statements, working papers, summaries, and reports are to be used as assessment tools at the Review Conference. Only the Review Conferences produce a consensus document. NGOs have become significant, visible, and important players at these conferences, and we have included the materials that they have circulated at these conferences as well. 

Originally intended as a temporary treaty, the NPT stipulates that 25 years after entry into force, a conference shall be convened to decide whether or not the Treaty shall continue indefinitely, or be extended for an additional fixed period or periods. In 1995, this conference was convened, and a package of decisions extend the Treaty indefinitely. Five years later, at the 2000 Review Conference all 187 governments - including the five official nuclear weapon states - agreed to 13 practical steps for the systematic and progressive disarmament of the world's nuclear weapons. At the 2005 Review Conference, states parties could not agree on a final document, and the five week long conference was considered to be a failure. In 2010, states parties adopted a 64-point action plan in order to move forward. However, their fulfilment of this action plan, in particular the disarmament requirements, is so far significantly lacking.