The uptake of HCI (human-computer interaction) and usability engineering by software development organisations can be terminally impeded by lack of appreciation of their value, even where ease of use is recognised as important. Descriptions of HCI offerings in terms of activities and methods are not readily comprehensible to managers of software products. Similarly, descriptions of HCI activities and methods give little indication of how these are to be managed with reference to the stages and deliverables in a software product development life cycle. This lack of clear association between usability engineering and software engineering in product development contributes to the marginalisation of usability-related activities. Specifying HCI or usability contributions to product development in terms of deliverables, on the other hand, can provide a solid basis for a manageable usability perspective on the development of software products. This article identifies a set of usability deliverables, describes their content and shows how they relate to a software product design and development process.