Use the Approval Workflow in the PO, Contract, RFI, Change Order and Payment Requisition modules of Contract Management.  

Pick an unlimited number of reviewers from the project's Contact list.

Once a Review Cycle is intitated, each reviewer will be notified in turn by e-mail that his or her approval is needed.  

Reviewers have a chance to add comments, and choose to approve or reject the document.

Reviewer approval and comments are recorded.

Once all the reviewers have approved the document, its status becomes 'Approved'.

Approvals can be revoked if necessary.

Revoking an approval will start a new approval phase.

View previous Review Cycles as necessary.