We present a summary of Chandra monitoring observations of M31, and partial results of our HST program to search for UV counterparts to M31 X-ray Transients. The first 8 epochs of monitoring spread over nearly 2 years reveals more than a dozen transient sources, with peak luminosities ranging from 1 × 10^37ergs sec-1 to 3 × 10^38ergs sec-1. While no definitive UV counterparts have yet been found, the X-ray brightest of these transients has the strongest candidate counterpart. The discovery of repeated outbursts from two of the transients yields new direct information on duty cycles of transients in M31. An unremarkable source with LX ~ 10^37ergs sec-1 may be associated with the galaxy's nuclear supermassive black hole (M31*). The cool temperature of the diffuse gas in the core of M31 ( ~0.35 keV), along with the high mass of M31*, indicate a Bondi-Hoyle accretion radius of ~arc-second scale. As well as being the closest supermassive black holes, M31* and Sgr A* may be among the few with Bondi-Hoyle radii which are resolvable with X-ray observations . This work supported by NASA grants GO2-3103X and HST-GO-9087.