Current CAD/CAE systems are not ideal for engineering design in distributed knowledge and intelligent resources. This paper investigates the approach of distributed collaborative design in service-oriented architecture. Service-ORiented Computing EnviRonment (SORCER) is employed to form a federation of distributed services that provide engineering data, applications and tools on a network. In order to implement interoperability between design services, standardized operation interface and design information transfer protocol should be developed for target domain. This paper introduces a standardized engineering layout design service interface to demonstrate the mechanism. We develop a flexible software architecture to organize services, to manage design process and to monitor design status in real time. This system aims to enable asynchronous distributed collaborative design with ease of alternative design services, reduced design cycles, and improved design resolution quality.