Dishonesty is fast becoming entrenched in commercial law in Australia as the defining characteristic distinguishing criminal conduct from conduct which only has civil or civil penalty consequences. Many of the serious offence provisions under the Corporations Act 2001 (Cth) require the prosecution to prove dishonesty and dishonesty has been adopted as a key element of the new cartel offence provision which is proposed for inclusion in the Trade Practices Act 1974 (Cth). Whilst deciding whether conduct is dishonest may be straightforward in most cases, situations can arise where a lawyer may be asked to advise a client as to whether a proposed course of conduct is dishonest and the answer may not be clear cut. Advising a client in such a situation may be difficult because current tests of dishonesty tend to reflect standards of ethics and morality generally accepted by the community which may not accord with the client’s and/or the lawyer’s personal standards. This article will examine the concept of dishonesty in the context of commercial crime, attempt to add some clarity to this particularly fluid concept and scrutinize the lawyers’ role in ensuring clients’ actions accord with community values.