After Iran confirmed allegations that it had secretly developed two undeclared nuclear facilities, diplomatic negotiations, beginning with the E-3 in 2003 (UK, France, and Germany) and expanding to US, China, and Russia (E3+3) in 2006, intensified. The aim was to secure Iranian cooperation with the International Atomic Energy Agency (IAEA) in assuring that its nuclear activities were in compliance with Nuclear Non-Proliferation treaty obligations, and for peaceful purposes only. Negotiations were one track of the "dual-track strategy" to address Iran's nuclear program, with Security Council sanctions constituting the second track to pressure Iran to suspend nuclear (enrichment, reprocessing, and heavy water) activities and provide assurances that there were no undeclared nuclear activities in Iran.
The analysis of the Iran case is divided into the following episodes (navigatable via the numbers in the top bar):
Episode 1 (23 Dec 2006 - 24 Mar 2007)
Episode 2 (24 Mar 2007 - 3 May 2008)
Episode 3 (3 May 2008 - 9 Jun 2010)
Episode 4 (9 Jun 2010 - 24 Nov 2013)
Episode 5 (24 Nov 2013 - 16 Jan 2016)
Episode 6 (16 Jan 2016 - Present)