A torque device for gripping and manipulating a guidewire for advancing the guidewire into a patient's vascular system. The torque device is configured for single-handed use and can be opened for repositioning the torque device relative to the guidewire and closed for gripping the guidewire to prevent axial and rotational movement relative to the guidewire. The torque device grips the guidewire at multiple spaced apart locations on the guidewire.