An electrophysiology catheter (20) comprises a shaft (22) having a first bending stiffness and a deflectable tip (28) secured to the distal end (24) of the shaft with a second bending stiffness less than the first bending stiffness. At least one electrode (34, 36) is mounted to the tip for delivering current to or monitoring electrical activity of tissue. A manipulator wire (58) is coupled to the distal end of the deflectable tip, whereby the deflectable tip may be deflected by axial force applied to the manipulator wire. A stiffener member (66) is axially slidable relative to the tip so as to adjust the tip curvature without removing the catheter from the body. The catheter may further include a core wire (72) configured to rotate the deflectable tip about a longitudinal axis (2) without rotating the proximal end (26) of the catheter shaft, wherein the distal end of the deflectable tip remains in a substantially constant axial position, preferably in a plane perpendicular to the longitudinal axis.