Geoff Sutcliffe and Juergen Zimmer and Stephan Schulz: Communication Formalisms for Automated Theorem Proving Tools Abstract This paper describes two communication formalisms for Automated Theorem Proving (ATP) tools. First, a problem and solution language has been designed. The language will be used for writing problems to be input to ATP systems, and for writing solutions output by ATP systems. Second, a hierarchy of result statuses, which adequately express the range of results output by ATP systems, has been established. These formalisms will support application and research in ATP, and will facilitate direct communication between ATP tools when they are used as embedded components in larger systems.