The content of the duties of honesty and propriety in Section 232 of the Corporations Law is examined. These duties have been held to provide a statutory expression and enforcement of fiduciary duties. Economic analysis is used to consider the implications of this. The limited liability corporation allows for specialization of management and risk bearing, although this advantage is attended by agency costs. Directors have an important function to fulfill in reducing these agency costs, but as agents themselves they need to be subjected to various controls, legal and otherwise. One of these is the fiduciary duties owed by directors. The use of fiduciary duties as the basis for penal law is potentially deficient, given their elasticity, their focus on matters that lead to divergences from efficient outcomes and the complication of ratification. These matters are exemplified by the duty of propriety in Section 232(6) of the Corporations Law, as recently interpreted by the High Court in R v. Byrnes, and to a lesser extent in Section 232(5).