These and other objects of the present invention are achieved in a body fluid sampling system for use on a tissue site that includes an electrically powered drive force generator. A penetrating member is operatively coupled to the force generator. The force generator moves the member along a path out of a housing having a penetrating member exit, into the tissue site, stops in the tissue site, and withdraws out of the tissue site. An analyte detecting member is positioned to receive fluid from a wound created by the penetrating member. The detection member is configured to determine a concentration of an analyte in the fluid using a sample of less than 1 .mu.L of the fluid.