In this paper we analyse an M/G (a,b)/1 queue with M different types of vacation polices. Whenever the server goes on vacation, he selects the ίth (1=1,2,…,M) type of vacation with probability αί(ί=1,2,…,M). The successive vacations are assumed to be independent but not necessarily identical. The Laplace transform of the joint distribution of the queue length and the remaining service time or the remaining vacation time depending on the state of the server is obtained. The marginal distribution of the queue length and the expected queue length are deduced.