Enable direct supervision of prisoners The prison’s supervision style is determined by both its management approach and its architectural layout, and is cited by researchers as one of the most important factors in affecting behaviour. There are two basic layouts: direct supervision and indirect supervision. In prisons with indirect supervision, staff and prisoners occupy separate territories. Supervision and control are remote and characterised by reliance on distant visual surveillance from secure staff stations, and on patrolling corridors and landings. Indirect supervision is reactive in nature, and tends to alienate prisoners and staff. With direct supervision prisons, staff areas are located inside the unit, so that staff have greater face to face contact with prisoners. These prisons are proactive rather than reactive, as their layout and the presence of staff lessen opportunities for misconduct. Research suggests that direct supervision allows more effective surveillance and better security, and results in a dramatic reduction in prison violence61. Direct supervision has also been endorsed by professional bodies, as well as the United Nations, as the best method for managing prisoners, including those classified as dangerous or disruptive. Allow flexibility/ adaptability in the use of the unit Positive architecture allows adaptability to future change. Planning can anticipate, and the design should include, the possibility of future alteration of internal spatial divisions, external additions or subtractions, and ‘functional flexibility’. New prefabricated technologies make it possible to design prison units so that they can serve different functions according to actual needs. So, for example, the division of space and design of a unit designated for long-term solitary confinement should not be so inflexible as to preclude the possibility of prisoner association areas or the provision of programmes, should there be a change in policies regarding the prisoners held in the unit or in their individual needs. Communicate a positive message The appearance of the prison communicates to prisoners how they are expected to behave (Wener, 2000:52). If the design and security arrangements in segregation and high security units communicate to prisoners that they are highly dangerous and not fit for human contact, they are more likely to start perceiving themselves as such and behave accordingly. Security arrangements should therefore be as limited and un-intrusive as possible and reflect the fact that segregated prisoners are already secured, individually, in their cells. It is also important to break the monotony of segregation units to allow a degree of sensory stimulation. This can be achieved easily and inexpensively by, for example, colourful wall paint, good lighting, and so on. 50 Sourcebook on solitary confinement: Design, physical conditions and regime in solitary confinement units