A lancing device having a drive mechanism whereby unidirectional motion of the drive mechanism drives a lancet along an advancing portion and a retraction portion of a lancing stroke. A rotationally mounted crank member or a translationally mounted shuttle of the drive mechanism operate upon an associated linkage and/or a cam path portion of the lancet carrier to drive the carrier along the lancing stroke. Spring biased members optionally drive the mechanism and/or limit its extent of travel.
