We present a rigorous but transparent semantics definition of the Spece language that covers the execution of Spece behaviors and their interaction with the kernel process. The semantics include wait, wai tfor, par, pipe, and try statements as they are introduced in Spece. We present our definition in form of distributed Abstract State Machine (ASM) rules reflecting the specification given in the Spece Language Reference Manual [ 5]. We mainly see our formal semantics in three application areas. First, it can be taken as a high-level, pseudo code-oriented specification for the implementation of a Spece simulator which is outlined in a separate section. Second, it is a concise, unambiguous description for documentation and standardization. Finally, it is a first step for Spece synthesis in order to identify similar concepts with other languages like VHDL and Systeme for the definition of common patterns and language subsets.