Pakrac was a city in Croatian region of Western Slavonia with mixed population - Croat and Serb. At the time of Serbian insurgency in Krajina in 1991, Pakrac became a city divided in two. Over a few years, with the help of international volunteers, local authorities on both sides overcame their hatreds and started cooperating, much to displeasure of their superiors. In August 1995 Croatian Army re-took Western Slavonia in the operation "Bljesak" ("lightning") and re-integrated Pakrac. Most of the Serbian population fled to Banja Luka. There is an independent report on that operation available from BALKAN MEDIA & POLICY MONITOR (issue 12 Vol 2 May 31, 1995). Today Pakrac is the site of MIRAMIDA project. There was, also, an APC/ZTN conference on the internet dealing with Pakrac and Slavonia.
Read about ZTN here.