Accounting policy‐makers continue to confront problems that arise from ambiguities in the value of some types of transaction. For example, AAS21 was put in place partially to ensure that assets of a business acquired are accounted for at fair market value, rather than at the values recorded in the books of the acquired business. One related question that has not been clarified is the value to be attributed to shares issued as a result of convertible note‐holders exercising conversion options. Convertible notes and convertible preference shares feature regularly in the capital structures of Australian firms. This paper discusses the economic nature of the conversion option, outlines alternative ways of accounting for conversion in the context of tax and other economic implications, and reports a brief survey of current pract