At present, none of the known mobility management proposals can efficiently support mobile wireless users in the Next Generation Network (NGN) because this environment will have both heterogeneous access technologies belonging to diverse network providers, and users using services with different network requirements. We aim to use Game Theory (GT) to understand how to fulfil the expectations of both users and network providers in a way that the NGN will work efficiently. In this work, we propose a game between the network operator and the users to evaluate how each user’s decision impacts on the operator reward, and vice-versa. In addition, we investigate how both players can maximize their rewards or utilities, noticing they have conflicting expectations. Then, we analyse distinct network usage scenarios: no user mobility, mobility detected by both operator and user, distinct user classes and various network loads. Our results show that our mobility model with heterogeneous users has a Nash Equilibrium (NE) but it depends on the network load, who triggers the handover and the handover management approach being used. In our opinion, these results give some guidelines as to how the NGN mobility should be supported.