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IADIS International Conference WWW/Internet 2010announcement, leader determination, objective announcement, negotiation setup, restriction announcement,core negotiation, commit attempt, contract (re)construction.Some works (Angelov & Grefen 2008b; Bacarin et al. 2008; Grefen et al. 2001) use e-contract template tofacilitate e-contract reuse. In a general way, the renegotiation issue is still not completely addressed in aproper way by the works proposed in the literature. Some architectures and frameworks (Angelov & Grefen2008a; Bacarin et al. 2008) allows contract update during process execution. However, none of themspecifies the actions to be performed in the case of contract violation. This work addresses the issue ofcontrol operations to handle contract enactment in the case of any clause violation.4. FEATURE AND WS-CONTRACT METAMODELSThe BPM context involves business process composed by e-services. Our approach considers e-servicesimplemented as Web Services and hence the WS-Contracts to regulate the collaboration between the parties.The WS-Contract is composed of: parties, e-services, contractual clauses and a business process. WS-BPELis used to define the parties and the orchestration of the e-services within an inter-organizational context(Alves et al. 2007). E-services and QoS attributes are described in WSDL and WS-Agreement, respectively.The WS-Contract metamodel, presented in Figure 1, represents the structure that supports the creation ofe-contracts. Originally, it was proposed by Fantinato et al. (2008) and was extended (in gray color) torepresent control operations. The metamodel comprises: i) Web Services described in the WSDL; ii)Business process specified in the WS-BPEL; iii) QoS attributes of Web Services, described inWS-Agreement; and, iv) Control operations to be handled in case of contract violation, also described inFigure 1. WS-Contract metamodelWS-Agreement.The WS-Contract is composed of three sections, as follows: WS-BPEL definitions: this section defines the business process using the terms Variable, PartnerLink and Activity (including Basic Activity and Structured Activity); WSDL definitions: this is the services section, it contains the base elements Message Type, PartnerLink Type, Port Type and Operation. The last two describe the Web Services; WS-Agreement definitions: it defines the business terms. The following elements are used todefine QoS levels: Service Property (including Variable) and Guarantee Term (including Service Scope,Service Level Objective and Business Value List). It includes also:- Control operations: represented within the WS-Agreement definitions, more specifically in theBusiness Value List section using the “penalty tags" as illustrated latter in Figure 3.A useful strategy explored here is the use of contract templates. An e-contract template is defined onlyonce, but allows instantiation of distinct and similar contracts. To facilitate the creation of templates,Fantinato et al. (2008) proposed a feature metamodel. It originally consisted of two sub-trees – e-services and5