This workbook is aimed mainly at university students, and it is designed to support work with Hammer's German Grammar and Usage, 5th edition, by Martin Durrell. The chapters move systematically through the main areas of German grammar and offer a maximally wide range of types of exercise. Straightforward gap-filling and transformation exercises are designed to practise the application of rules, and more complex exercises from authentic sources give a sense of the ways in which those rules work in the context of day-to-day communication. Open-ended 'Projects' encourage independent study and analysis.