4.39.3 Because the Joint Committee can only exercise the powers which are given to it by each constituent authority, each authority can limit the Joint Committee by limiting the powers which are delegated to the Joint Committee. It can do this by delegating general powers, but then providing that certain critical decisions are reserved for the approval of the individual authorities, for example the approval of the OBC for a PFI project. Or it can provide that the delegated powers are not to be exercised where an authority has signalled its objection to a proposed decision. Or it can set preconditions, such as saying that it does not delegate powers to the Joint Committee where they involve a course which is unacceptable to the particular authority in a specified way. This latter option needs to be exercised with care, as there is no point in setting up a Joint Committee to pursue a project where one or more of the authorities have already ruled out what may be the most viable option.