Lower limb prosthesis for above or lower knee amputees are still designed and manufactured almost completely in a manual way, deeply relying on the experience and manual skills of orthopaedic technicians. Such a nonrepeatable non-deterministic procedure is poorly efficient and time consuming and patients may have to wait for a considerable amount of time before getting a new, hopefully better, prosthesis. The proposed paper shows the main features characterizing the working prototype of a virtual environment developed to assist the technicians in the creation and test of the virtual prosthesis. To reach the ambitious goal of replacing the manual process with a virtual one several issues have been considered and addressed: the capture and formalization of process knowledge of orthopaedic technicians, the acquisition of patient’s information and digital data also by means of diagnostic instruments, the development of integrated solution to design and test standard and custom-fit components and the use of digital human techniques to simulate the way the prosthesis will behave during walking. The architecture of the integrated environment will be described in the paper and the main tools will be briefly introduced in order to illustrate the most important steps creating an uninterrupted path going from patient’s history and MRI data to the creation of his/her avatar wearing the new digital prosthesis, virtually trying it, setting it up and passing data for automatic production.