Challenging behaviour (also known as behaviours which challenge services) is defined as "culturally abnormal behaviour(s) of such intensity, frequency or duration that the physical safety of the person or others is placed in serious jeopardy, or behaviour which is likely to seriously limit or deny access to the use of ordinary community facilities"."Ordinarily we would expect the person to have shown the pattern of behaviour that presents such a challenge to services for a considerable period of time. Severely challenging behaviour is not a transient phenomenon."