Defence date: 23 October 2019Examining Board: Prof. Ramon Marimon, European University Institute, (Supervisor); Prof. Juan Dolado, Universidad Carlos III; Prof. Gaetano Gaballo, HEC, Paris; Prof. Thomas Sampson, LSEThis thesis contains three chapters. The first two consider deviations from rational expectations for understanding the unprecedentedly long period of a binding zero lower bound (ZLB) since the Great Recession. There I show that if agents are adaptively learning, Central Banks can use forward guidance to guide them through the novel economic environment. In the third chapter I take a more long-run structural outlook to study the interplay of skills, technologies and complementarities for understanding differences in labour ma...