To understand how tax authorities are adapting to operational changes and adhering to best practices—or failing to do so—McK gathered a new set of qualitative and quantitative insights. Their research, primarily derived from their Tax Administration Performance Benchmark includes data from 21 national and state tax authorities around the world. The research highlights four areas of divergence where the practices of leading tax authorities are significantly more advanced than others: digitizing interactions with taxpayers, advanced analytics, process automation, and talent management. This research shows that most tax authorities have made some progress in at least one of these areas—however, no institution is leading in all dimensions, and even those in the lead are continuing to innovate and capture significant gains. Much can be learned, therefore, from the different choices made by tax authorities on what to accelerate.