This report details the development of computer software to teach English-as-a-Second-Language skills for medical diagnosis. Design of a prototype unit of multimedia materials using a common authoring tool required about 300 hours of work over a period of 9 months. The report describes the overall design of the courseware, hardware used, stages of development (preliminary planning, choice of authoring software, structuring and creation of the activity, graphics and sound, programming), planned improvements, problems and issues encountered, piloting with five learners, and time requirements for software development. General issues that needed to be addressed during the process included: minimization of user anxiety; effective screen layout and color use; the format to be use to simulate doctor-patient interaction; the degree of freedom to give the learner in manipulating the materials; and efficient learner navigation through the materials. It is concluded that while creation of this program was time-consuming, much was learned and the development of additional courseware will be more efficient. (Contains 26 references.) (MSE)