Large scale application of the II- VI compound ZnSe has been hamperedrnby the low conductivity of p-type ZnSe. Very recently, well-conducting p-typernZnSesamples' Jlave been produced, but it is still not known wlty acceptor dopingrnof ZnSe is so difficult. Nonetlteless, intrinsic point defects and impurities arernblamed for tltis problelltrnIn the ZnSe semiconductor doped witlt In, the formation of Inzn - Vznrncomple.-.:es is shown to o~cur .u sing. tlte radioactive dopant 1lJ In along witlt tlternperturbed rr angular correlation technique wlticlt seem to be responsible for tlternself-compensation of In donors in ZnSe. Tlte. formati.o n and dissociation ofrnthese comple.-.:es were observed following a rapid quench of the material duringrnannealing between 300 and 700 Kin vacuullt In light of tltis tltermal stabilityrn,rnof tlte complex, the migration energy of the metal vacancy defect Vzn and itsrnbinding energy with the donor In is determined to be 1.30 ± 0.05 eV and 0.34 ±rn0.03 e V rj!spectively