A minimally invasive surgical system includes a guide tube and a telemanipulatively controlled surgical retractor instrument that extends through the guide tube. The portion of the retractor instrument that extends beyond the distal end of the guide tube includes several links that can be steered. In some aspects, joints between the links provide degrees of freedom in the same direction of movement. In some aspects, a grasping end effector is coupled to the end of the retractor instrument, and in further aspects the grasping end effector is coupled by a passively rotating wrist mechanism that rotates as the retractor instrument is moved while the end effector grasps tissue.