The Read Codes are a hierarchically-arranged controlled clinical vocabulary introduced in the early 1980s and now consisting of three maintained versions of differing complexity. The code sets are dynamic, and are updated quarterly in response to requests from users including clinicians in both primary and secondary care, software suppliers, and advice from a network of specialist healthcare professionals. The codes' continual evolution of content, both across and within versions, highlights tensions between different users and uses of coded clinical data. Internal processes, external interactions and new structural features implemented by the NHS Centre for Coding and Classification (NHSCCC) for user interactive maintenance of the Read Codes are described, and over 2000 items of user feedback episodes received over a 15-month period are analysed.

The goal of the PEN&PAD project is to design and develop a useful and usable medical workstation for day–to–day use in patient care. The project has adopted a user centred approach and direct observations of doctors, participative design and Formative Evaluation have therefore been an integral part of the process of software development. Indeed, doctors have been involved from the earliest stages of the project. The project has focussed on British General Practitioners, but the methods which have been evolved are general. This paper describes the strategy by which doctors can be involved in the successful design and development of a medical workstation.