As there has been substantial increase in the number of multicenter clinical trials in Korea, sponsors and investigators are concerned about the duplication of effort and delay by multiple IRB reviews. To enhance the efficiency of IRB in multicenter studies, the introduction of joint IRB or central IRB has been discussed. Although the Korean Good Clinical Practice(KGCP) was revised to accept centralized IRB review process in 2007, joint IRB has not been used in most institutions. Two models of joint IRB, single non-profit IRB and multiple lead IRBs, are applicable considering the current situations of IRB in Korea. The concept and operation of the two models have been described in this article. The governmental initiative and operational guidelines are the prerequisites for the successful implementation of the nationwide joint IRB in Korea.