Adaptivity in training software systems is of great importance as it can adjust one single training environment to the needs of each individual trainee. ASSET is such a UML training software system as it provides adaptive support to both the trainer and the trainees. Specifically, it provides an environment that can be parameterised by the trainer to suit the training needs of his/her company or educational institution. The adaptive help to the trainer concerns mainly advice on the best schemes of collaboration between the trainees and the most efficient and productive forming of group as well. The adaptive help destined for the trainee refers to knowledge, user type and personality attributes. The special characteristic of ASSET is that it does not base its inferences on specific tests, but constantly monitors every action of the trainees during their interaction with the system.