In times of globalisation, more and more lecturers with other first languages than English have to - or would like to - give lectures, seminars, and presentations in English. This book discusses issues that need attention when individuals and institutions switch to English-medium teaching in higher education. Numerous questions invite readers to reflect on areas ranging from individual instructors' prerequisites to cultural diversity and policy issues. The practical part contains activities, strategies, and resources for clear and effective English-medium teaching. It is rounded off by a glossary with useful words and phrases for teaching, classroom management, and oral exams.