A guidewire formed at least in part of a superelastic member with a section having one or more altered properties including physical and mechanical properties. Preferably, the section of altered property has reduced superelasticity with respect to the remainder of the superelastic member. The invention also comprises method of manufacturing such guidewires wherein a section of the superelastic member is isolated and treated to change one or more of the properties. The treatment may be alloying with a diffusable element or isolating one or more sections to work and heat treat to decrease superelasticity relative to the rest of the member. The section having one or more altered properties is preferably a distal portion of the member, for example about the most distal 3 cm.
