We present Large Angle Spectrometric Coronagraph (LASCO) observations of two events that suggest magnetic disconnection in coronal streamers. During the 1--2 days preceding each event, successions of narrow looptops are seen rising slowly through the 2--6 RS field of view, forming a bright streamer stalk which continues to elongate with time. As the streamer becomes ever more constricted, it eventually severs at a heliocentric distance of ~4 RS. The lower part of the stalk collapses back to form a cusplike structure extending to ~3 RS, while the disconnected segment is observed as a kink or density enhancement that propagates outward with a speed of order 200 km s-1. We interpret these non-CME events as transient openings and closings of magnetic flux rooted at the boundaries of coronal holes. ¿ 1999 American Geophysical Union