The objective of this study was to assess the effect of four different nurse staffing strategies on hospital costs: Part-time RNs; RN temporary agencies; RN rich skill mix; and organizationally experienced RNs. Two regression equations were specified to consider the effect of these strategies on personnel and benefit costs and on non-personnel operating costs. A number of additional variables were also included in the equations to control for the effect of other organization and environmental causes of hospital costs. Consistent with the hypotheses, use of part-time RNs and experienced staff reduced personnel and benefit costs while the use of temporary agencies for RNs increased non-personnel operating costs. An RN rich skill mix was not related to either measure of hospital costs. The implications of our findings for hospital administration are discussed.