This paper deals with developing and assessing the training of physicians to deliver a difficult diagnosis to patients. The training is provided by a web-based self-training package. This online training emphasizes the structural, functional and relational dimensions of interviews delivering a serious diagnosis, and a logical set of recommendations for behavior towards the patient. The content is illustrated by numerous delivery interview sequences that are described and for which commentary is provided. This online package was expected to enable physicians to acquire new skills and change their mental picture of diagnosis delivery. Here we discuss the assessment of training in managing the delivery of a serious diagnosis. The approach taken and the methods used to measure knowledge and skills are presented.