This document summarizes the IAB Adex Benchmark 2012 study on the European online advertising market. It found that the total value of the European online ad market in 2012 was €24.3 billion, an 11.5% increase from 2011. Search advertising continued to be the largest format with 48.8% of total online ad revenues, though display and classifieds/directories also saw growth. The top 5 European markets (UK, Germany, France, Spain, Italy) accounted for over two-thirds of total online ad spend. Growth was strongest in Central and Eastern European countries but many Western European countries also saw sustained high growth rates. The report predicts future growth will be driven by increases in mobile, video, and real-