Apparatus (10) for locating an ostium of a branch vessel includes a delivery- catheter (12) having a distal end (16) sized for introduction into the branch, and locator elements (50) including first ends (52) fixed to the distal end (16) and second ends (54) free from the distal end (16). The locator elements (50) are compressible from a transverse, deployed condition to an axial, contracted condition, wherein the second ends (54) are disposed proximal to the first ends (52). The catheter (12) may be used to deliver a stent (40) into the branch with the expanded locator element (50) facilitating positioning the stent (40).