We develop a game semantics for process algebra with two interacting agents. The purpose of our semantics is to make manifest the role of knowledge and information flow in the interactions between agents and to control the information available to interacting agents. We define games and strategies on process algebras, so that two agents interacting according to their strategies determine the execution of the process, replacing the traditional scheduler. We show that different restrictions on strategies represent different amounts of information being available to a scheduler. We also show that a certain class of strategies corresponds to the syntactic schedulers of Chatzikokolakis and Palamidessi, which were developed to overcome problems with traditional schedulers modelling interaction. The restrictions on these strategies have an explicit epistemic flavor.