Bringing debates surrounding teacher expertise into conversation with wider debates surrounding expertise, Jessica Gerrard and Jessica Holloway reflect on recent events, including COVID-19 and the climate crisis. Drawing on international research, this book places experience within global context, attending to the ways in which teacher expertise itself is subject to struggles and contestations in power in different ways across different national and sub-national contexts. Through illustrative examples taken from this research, this book shows how expertise is as much about who is understood to be an expert, and who is understood not to be. Expertise sheds timely light on the contradictory and ambivalent practices of expertise.