How does an animal's nervous system select and generate an appropriate behavior for each circumstance the animal faces?  My research addresses this general question through neurophysiological and neuroanatomical experiments on an especially suitable model system:  the turtle spinal cord.  The turtle spinal cord can produce three distinct types of rhythmic scratching movements of a hindlimb, each targeted to a different region of the body, as well as two types of rhythmic swimming movements of the hindlimbs.  The programs for generating these movements and for "choosing" among them reside in the spinal cord:  the animal can produce these movements appropriately even when all input from the brain is cut off.  This means we can focus attention on a relatively small subset of the central nervous system (CNS) and study the electrical activity and the morphology of individual spinal cord neurons that are involved in selecting and generating each type of movement.  We can then reveal the kinds of neural circuitry that allow the spinal cord to select and generate appropriate movements.