Abstract: A side-firing laser fiber is provided with a directional indicator for use in determining the orientation of radiation to be emitted from the laser fiber. The laser fiber has an elongate core clad with a nylon jacket. Over a portion of the nylon jacket is placed a sleeve of heat shrinkable material. The sleeve is positioned over the jacket near the distal end of the laser fiber and is heat treated as to be joined to the laser fiber. Biocompatible ink is then applied to the sleeve to form a linear marking capable of delineating the direction of radiation to be emitted from the side-firing laser fiber. In use, the linear marking is oriented in the direction in which the radiation is to be emitted and the laser is then activated. This technique is particularly useful when the distal end of the side-firing laser fiber is obscured from view. The portion of the laser fiber to which the sleeve is attached is still visible when the distal end of the laser fiber is obscured.