Outline of the plan
The plan was meant to allow for the reintegration of the Republic of Serbian Krajina into Croatia by offering wide-ranging autonomy through most of Serbian Krajina. In addition, the plan called for the return of all croatian refugees. However, the plan would have required UNPROFOR to extend its mandate in order to implement the agreement, and the Croatian constitution would have to have been amended to accommodate the requirements of autonomy.
Some aspects of the proposed autonomy included the following:
Total monetary independence, which would have included fiscal policy and a separate currency pegged to the Kuna.
Krajina would have been a free trade area with no tariffs; this was meant to encourage economic growth in Krajina.
Elements of statehood including a coat of arms, flag, anthem, and police.
Eastern Slavonia, Western Srem, and Baranja would not have been included as part of the autonomous Krajina but would have undergone a separate reintegration process and would have had the presence of international troops for a period of five years. It was intended that this region would not be given a special status. Croatia would have regained control of the region after 5 years, in which an agreement with Croatian authorities would have been reached and the region would have been demilitarized (with the exception of a 5 kilometer zone along the international border and the Danube).
The 11 municipalities that had Serbian majorities in the 1981 census would have been given a special status and been called “Serbian Krajina”. Pursuant to constitutional law, these municipalities formed the districts of Krajina and Glina.
The constitution and laws of the Republic of Croatia would have been valid on the territory of Krajina, but they would have to have been approved and implemented by the local authorities.
Krajina would have had an election of the president of Krajina.
Krajina would have been demilitarized and the Croatian army could enter it only if called by the president of Krajina.
No official in Krajina would have been responsible to any authority in Croatia.
Source:
http://en.wikipedia.org/wiki/Z-4_plan