 Completely denying the existence and value of supererogatory action does not fit with most people’s intuitions. One way to account for supererogation without giving up the moral and theoretical principle relating the ‘good’ to the ‘ought’, value to duty, is to distinguish between different kinds of duties and obligations or to specify conditions and limits of the application of duties. Supererogation is a legitimate class of moral action but only in a qualified sense, i.e. due to certain conditions that make the moral ‘ought’ inapplicable or not fully prescriptive. This intermediate position seems to be the most common in the literature on supererogation, but it has many forms and variations.