The formalism of temporal logic has been suggested to be an appropriate tool for expressing the semantics of concurrent programs. This paper is concerned with the application of temporal logic to the specification of factors affecting the synchronization of concurrent processes. Towards this end, we first introduce a model for synchronization and axiomatize its behavior. SYSL, a very high-level language for specifying synchronization properties, is then described. It is designed using the primitives of temporal logic and features constructs to express properties that affect synchronization in a fairly natural and modular fashion. Since the statements in the language have intuitive interpretations, specifications are humanly readable. In addition, since they possess appropriate formal semantics, unambiguous specifications result.