Hi, someone just asked me this on MSN and it's bugging me, here's the question 30 card players want to play in 6 groups of 5 every month, such that no player ever plays with another player again in a subsequent month. What is the maximum number of months that the players could play under these rules? Why? I'm not sure where to start and solve it really, first thoughts tell me permutations but can't really see how to do it, I've been out of this game for too long ! Any help would be appreciated, thanks in advance.