The management side of "O'Leary Manager 2000" is very comprehensive when compared to similar Game Boy Color games. The player can choose from 240 fully licensed teams from the top two leagues in England, France, Italy, Spain, Germany and the Netherlands to play as or manage, with each team having 16 players in their squad. There is also the option to promote a number of fictional youth team players. However, most of the youth team players are of low ability, so could only realistically be used for back-up when managing a decent quality team.