In this paper the role of staffing levels as a determinant of seclusion use in one psychiatric hospital is examined A detailed review of the official records of seclusion over a 2-year period was completed (n= 225) The staffing levels on shifts when seclusions were initiated were compared with similar shifts when seclusions were not used on the same ward Statistical analysis revealed a highly significant difference between the levels of staffing Wilcoxon matched pairs signed-ranks test, Z=-5 8675, two-tailed, P= 0 001 This finding suggests that staffing levels play a crucial role in the practice of seclusion However, the overall staffing level must be considered along with other factors in the makeup of the staff group, including the ratio of female to male staff and the experience level of those staff These findings have important implications for those involved in the management and practice of seclusion as well as the patients who are secluded