Abstract: Guidewire system includes a guidewire jacket, at least two guidewires, and a handle. The guidewires are initially constraint within the guidewire jacket and may be introduced into a diagnostic or other catheter to deliver the guidewires to a target region in a patient's vasculature. The handle detachably retains the guidewires so that they may be advanced simultaneously with the guidewire jacket. The guidewires may be then detached and manipulated individually to locate them properly within the region. After removing the guidewire jacket and the diagnostic catheter, the two or more guidewires provide a trackable yet flexible path for the introduction of interventional catheter or sheath.