This study was designed to determine whether a change from a task-oriented care approach to a client-oriented care approach affects (a) the level of agitation and (b) 24-hour sleep in residents suffering from dementia in a nursing home. The levels of dementia and sleep of 33 nursing home residents were measured four times over 12 weeks (twice before and twice after the change in care approach) using the Cohen-Mansfield agitation inventory and the dementia mood assessment scale. Verbal agitation levels significantly decreased 6 to 8 weeks following the change, whereas more infrequent agitated behaviours, which were classified as 'other', significantly increased. Daytime sleep increased initially after the change but then returned to baseline levels after 6 weeks. While the main focus of the study was on residents' behaviour following an environmental manipulation, anecdotal observations of staff members interactions with residents indicated that they felt less rushed and were more tolerant of residents' behaviour following the intervention.