A guide for controlling the orientation of a medical device includes a cannula having a lumen therein for the medical device, and a guide member having a passage therein for receiving and directing the medical device, the guide member being movably mounted in the cannula for movement. The guide member can be magnetically responsive to an externally applied magnetic field, or can be magnetically responsive to an externally applied magnetic field when a magnetic medical device is in the passage, and/or it can be mechanically responsive.