The Web Service Level Agreement (WSLA) is a Web Service specification language developed to provide a SLA template to capture all the information negotiated and agreed upon by a service provider and service consumer. Though this specification is suitable for many Business-to-Business collaborations involving two parties, it does not fulfil the requirement of a new business model involving multiple parties, where a party provides multiple services to other parties and consumes services provided by other parties. To address this requirement, this paper proposes an extension to the WSLA language to capture multi-party collaborations, called WSLA+.