The purpose of this paper is to illustrate some of the ways in which new, specially designed supply side studies can be linked to the more familiar demand side financial access surveys to enrich and complement the findings of those demand side surveys. In particular these supply side studies may help explain issues and anomalies in the demand side data. Oxford Policy Management has experimented with this methodology in Kenya, Tanzania, and Zambia. Examples are given of five areas in which this integrated approach has enriched the findings of demand side surveys in those countries: affordability and cost structures; the impact of population density and poverty; levels of monetisation; the classification of suppliers and overlaps between suppliers; and the impact of cultural differences.