  Many clues about the galaxy assembly process lurk in the faint outer regions
of galaxies. Although quantitative study of these parts has been severely
limited in the past, breakthroughs are now being made thanks to the combination
of wide-area star counts, deep HST imagery and 8-m class spectroscopy. I
highlight here some recent progress made on deciphering the fossil record
encoded in the outskirts of our nearest large neighbours, M31 and M33.
