This month will see the enforcement of a sweeping new set of regulations that could change the face of digital marketing: the European Union’s General Data Protection Regulation, or GDPR. To protect consumers’ privacy and give them greater control over how their data is collected and used, GDPR requires marketers to secure explicit permission for data-use activities within the EU. With new and substantial constraints on what had been largely unregulated data-collection practices, marketers will have to find ways to target digital ads, depending less (or not at all) on hoovering up quantities of behavioral data.