Endovascular repair of aortic abdominal aneurysms (AAA) is more and more becoming part of clinical practice. Up to approximately 30 clinical procedures however are necessary to obtain the surgical skills to make the procedure reliable and safe. The current study aims to generate a VR trainer to speed up the training process of experienced vascular surgeons to become experienced EVAR (endovascular AAA repair) surgeons by introducing a VR environment. This manuscript describes the contents and validation of the first step in the VREST - EVAR trainer, i.e. the proper definition of the knowledge and skills that need to be transferred.