In this paper, we describe the development of a virtual human to be used for training applications in the field of cardiac emergencies. The system integrates AI techniques for simulating medical conditions (shock states) with a realistic visual simulation of the patient in a 3D environment representing an ER roomIt uses qualitative simulation of the cardio-vascular system to generate clinical syndromes and simulate the consequences of the trainee’s therapeutic interventions. The use of knowledge-based simulation provides a strong basis to integrate the behavioural aspects with the graphical appearance of the patient in the virtual ER. This also supports the creation of an emotional atmosphere increasing the realism of the training system. Categories and Subject Descriptors J.3 [Life and Medical Sciences]: Medical Info Systems. General Terms: Human Factors, Design.