Projected just outside the centre of Arnhem in a public park at a bend in the River Rhine, is this centre for psychotherapy. The building may be conceived of as a transformation of the traditional monastery which served around 1800 as the first bona fide accommodation for psychiatric patients. Both the design and the choice of site proceeded from a specific function: that of the clinic for behaviour therapy. With only a few of their kind in the Netherlands, such clinics work to a philosophy predicated on the possibilities of conditioning human behaviour. Treatment is brief, intense and geared to the individual. Contact with the surroundings and with society have a major part to play in the treatment. These characteristics of behaviour therapy are worked up into two themes. The first, movement, is linked to the process of treatment as it unfolds and the rapid changes patients are thereby subjected to. The second is the patient's confrontation with him/herself and with the (built) environment. Both themes underpin the design and its detail development. The centre for psychotherapy divides into two levels - one for staff, the other for patients - that interlock in a double L-shape. The entire building can be read as a single route of spatial exercises to support the therapy, ranging from introverted at the internal court to extravert at the front facade with its view out over the town. This route broadens in parallel with the patients' perception as therapy proceeds. This way, manipulability of the spatial conditions increases as the detailing of the spaces develops from invisible to clearly organized. Such transformations serve to slot the building into its surroundings, responding as it does to the billowing height lines, the bend in the Rijn and the prospect of Arnhem. The zinc roofscape, the natural landscape of the Veluwe region and the rippling surface of the river blend one into the other. Institution: TU Delft Tutors: Daan Vitner, Frank Koopman, Jan Engels & Erik van der Kooy Specialization: architecture