Abstract: A writing instrument having a casing with an axially-extending bore seating a cantilevered arm of a pocket clip which protrudes through the casing bore when the instrument is in an "off" position. The pocket clip has guide tabs which fit into guide channels in the instrument's casing. The guide channels, with spring fingers which bias the pocket clip in the direction of the bore, are capable of releasably locking the clip in plural positions. In the "off" position the pocket clip arm protrudes through the casing aperture but the writing members housed within the casing are retracted. Moving the pocket clip to a "write" position causes a writing member to project from either the front or back of the housing and the pocket clip arm to be retracted into the casing.