This paper analyzes layer 2 contention resolution strategies for wireless networks with multipacket reception by using noncooperative game theory. Necessary and sufficient conditions are obtained for a strategy profile to be a Nash equilibrium. Applications of the derived equilibrium conditions to predict selfish behavior and the resulting equilibrium performance are illustrated in specific communication scenarios along with various design insights. The collective equilibrium behavior of wireless networks with large user populations is also studied, and a Poisson-Bernoulli type approximation is obtained for the total number of packet arrivals. Finally, random access control with imperfect information structure is considered, the form of equilibrium strategies as well as uniqueness and existence results for general wireless channel models are obtained, and the best-response learning dynamics achieving an equilibrium are illustrated in specific instances.