Over one quarter of a million single people in Sydney live alone in one-person households. Another 150,000 or more live as non-family household groups. While most of these live in groups of two, about 20,000 of them live in groups of 4 or more. (This in itself requires a stock of about 4,000 dwelling units.) Until now, no organisation has seen a need to research this group. However, investigation of the unpublished Census data shows it is difficult to identify sharing groups (since this class of information has not been specifically sought in the Census). In addition, the Census definition of ‘dwelling’ makes it possible for two (or more) families sharing a single house or flat to show up in the Census as occupying two (or more) “dwellings” thus possibly concealing a group of disadvantaged families.