This invention relates to devices for navigating passageways in a body, and in particular, to a steerable catheter that can be used to navigate the tortuous anatomy of a body's vasculature. In one embodiment of the invention the deflectable catheter comprises an inner catheter body having a first strut spine member and a cantilevered second strut tang member. An outer catheter body is cooperatively associated with the second strut tang member and an actuator is cooperatively associated with the first strut spine member. The actuator is slideably engaged within the outer catheter body.