Tangena JAA, Hendriks CMJ, Devine M, et al. - In 2006, the World Health Organization (WHO) stated that countries should report on coverage and impact of indoor residual spraying (IRS), a key tool for controlling and eliminating malaria by targeting vectors, data on IRS coverage are still sparse and unspecific. Researchers, here, reported on the subnational coverage of IRS across sub-Saharan Africa for the four main insecticide classes from 1997 to 2017. A variety of sources, including the President’s Malaria Initiative spray reports and National Malaria Control Programme reports, were analyzed for data on IRS deployment for all 46 malaria-endemic countries in sub-Saharan Africa from 1997 to 2017. Observations revealed a considerable increase in the number of countries implementing IRS over time, although the focal nature of deployment means the number of people protected remains low. From 1997 to 2010, DDT and pyrethroids were commonly used, thereafter these were partly replaced by carbamates from 2011 and by organophosphates from 2013. Since the publication of resistance management guidelines, overlap between pyrethroid IRS and ITN use has been typically avoided in IRS deployment. However, no routine use of annual rotations of insecticide classes with differing modes of action was observed.