2016 has truly shown how dynamic an ecosystem the digital advertising industry is. There have been highs and lows, but it has certainly been memorable. In a series of features reflecting on the past year and looking ahead to what we can expect in 2017, ExchangeWire invite over 100 thought leaders from across the industry to share their views. In the latest series instalment, experts deliver their opinions on the broader industry challenges that have grabbed the headlines in 2016 and how their stories will develop in 2017.