This document analyzes data on cartel enforcement and dominance investigations from competition authorities around the world in 2015. It finds that the US Department of Justice issued the largest total cartel fines, driven largely by a foreign exchange rate collusion case. The European Commission had a relatively slow year for cartel fines. Many authorities conducted few or no dawn raids or issued small cartel fines. Leading authorities are increasingly investigating potential anticompetitive conduct by technology companies in relation to issues like data collection and use.