Lumbar puncture for purposes of administering spinal or epidural anesthesia is a complex clinical skill which requires the clinician to precisely correlate a detailed mental map of hidden three-dimensional anatomy with tactile feedback from the spinal needle as it's being inserted. At Dartmouth, a collaborative work between the engineering and medical schools is aimed at developing a computer-based simulation utilizing high-resolution 3D graphics and a force-feedback device to simulate the "feel" of inserting the needle. This paper describes the mechanical design, hardware and software issues and some of the technical challenges being addressed in this project.>