The outburst of the unusual variable star V838 Monocerotis is being accompanied by the most spectacular display of light echoes in the history of astronomy. We have imaged the echoes on 5 occasions in 2002 with the Hubble Space Telescope and its Advanced Camera for Surveys. Analysis of the angular expansion rates and polarimetry data yields a direct geometric distance (6 kpc), and establishes that the star was extremely luminous at the maximum of its outburst. Unlike a classical nova, V838 Mon has remained a very cool red supergiant, and is now producing copious amounts of dust. The dust illuminated in the echoes was presumably ejected during previous similar outbursts. This event thus bears some similarities to the proto-PN ejection process from more normal AGB and post-AGB stars, and is of relevance to this conference. Light-echo imaging allows construction of fully 3-D maps of the dust distribution, and we present a map based on these early observations. The dust is already seen to be highly non-spherical and non-homogeneous, similar to the structure inferred for many proto-PNe.
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