This volume examines the impact of burrowing animals on the environment, over a wide range of taxa - ants, beetles, wood-borers, nematodes, fish, rabbits, badgers, rats - paying equal attention to terrestrial and aquatic habitats. Burrowing activities have significant environmental effects, such as increased soil fertility, changes in plant abundance and distribution, increased chemical interchange across the sediment-water interface, and alterations in soil and sediment stability. The scale and importance of animal burrowing are made clearer than ever before by the contributors to this symposium.