Background: The imbalance between the sheer size of the developing world and what little is known about the lives and life circumstances of persons with disabilities living there should command our attention. Method: International development initiatives routinely give great priority to the collection of statistical indicators yet even the most basic data on intellectual disability is lacking. In response to the recent adoption of the ‘international classification of function’, numerous initiatives are attempting to expand and improve the quality of disability surveillance. Results: We argue that these efforts must not lose sight of the core focus and promise of disability statistics – that of advocacy and the elevation of a disability policy agenda. Conclusions: To this end, we weave throughout our analysis of the technical features of surveillance, reflections on the meanings we attach to disability statistics and by extension, disability itself.