1. 1 Purpose and Plan of This Review This review is focused on the topography and connections of some of the neuron populations that determine the manual dexterity of the macaque monkey. The populations selected for examination are the following: 1. The corticospinal neuron populations 2. The thalamocortical and corticothalamic neuron populations associated with the sensorimotor cortex 3. The ipsilateral cortical connections of the sensorimotor cortex These neuron populations have been chosen because of their obvious rel- evance to the directed, intelligent use of the hands, but also because...