A modular catheter includes an elongate tubular member having a proximal end and a closed, distal end. A lumen extends from the proximal end to the distal end and a plurality of electrodes are arranged at, or adjacent, the distal end, conductors for the electrodes being contained within a wall of the tubular member. An elongate shape-imparting mechanism is removably received within the lumen of the tubular member such that a distal end of the shape-imparting mechanism is substantially in register with the distal end of the tubular member. A control device has a proximal end and a distal end, the proximal end of the tubular member and a proximal end of the shape-imparting mechanism being releasably connectable to the distal end of the control device.