As part of the verification, Bureau Veritas undertook: • interviews with relevant personnel of WPP responsible for GHG emissions accounting and employment data; • a review of WPP information systems and methodology for data collection, aggregation, and analysis; • a review of information and calculations used to determine GHG emissions; • sampling of source data from energy consumption, geographical location and head count; • audit visits to five of WPP’s operations: WPP Corporate London, J. Walter Thompson London, Kantar UK, Kantar Germany, MediaCom UK, to review underlying systems for collecting and reporting employment and emissions data; and • a review of the consolidated 2015 data to check end of year accounting and reliable transposition.