The 2013 call of the High Level Panel on Post-2015 for a ‘data revolution’, echoed in the recent report of the Independent Expert Advisory Group (IEAG) on the data revolution, has given renewed impetus to data collection efforts to ensure that ‘no one is left behind’. Household surveys are the workhorse of MDG data reporting efforts and this is likely to remain the case under a new post-2015 agreement. However, because these instruments focus on the household as the unit of data collection, they generally exclude people living in other settings – be it on the streets, in refugee camps, in residential care homes or in correctional facilities. Our analysis of living standards and of well-being, therefore, reflects these exclusions. This paper considers who is excluded and why, the potential costs of such exclusion for monitoring and policy, and ways it could be redressed.