Abstract: A locally synchronous circuit module has a delay circuit having and input and output coupled to a clock input. The delay circuit provides a delay which when incorporated in a clock oscillator ensures a clock period that is at least as long as needed to transfer information between the storage elements. A handshake circuit is provided for generating handshake signals for timing information transfer between the locally synchronous circuit module and a further circuit. The handshake circuit comprises the delay circuit, so that at least part of the handshake signals during a handshake transaction are timed by travelling through the delay circuit and are applied to the clock input to clock the locally synchronous circuit module.