A major problem facing organizations using grid-computing models is the reluctance to participate in multi-organizational collaborative environments due to security concerns, such as unauthorized access, and fair resource usage. The Joint control of Virtual Organizations (JoVO) framework enables organizations to form a unified VO, with jointly agreed, knowable and enforceable security policies. The JoVO framework is based on the fault and intrusion tolerant joint control of identity, attributes, and access control policy through the use of threshold-based certification authorities. We propose a set of agents, the Credential Management Agent and Identity and Authorization Agent to aid grid services when operating in a multi-domain environment. One of the key areas of concern in grid computing is the assurance of all parties involved that security policies are appropriate and will be enforced. We propose an automated distributed audit agent framework consisting of white-box and black-box service testing for joint validation of access control policy.