This book fills in the gap in publications on the modelling and design of external gear pumps with modified tooth profile. It is dedicated to designers, technologists and researchers, but also to students who want to broaden their knowledge of hydraulic drives and controls. The book is a synthesis of the knowledge about the structure of pumps and technology of manufacturing gears. Special attention is devoted to an original tooth root relief and modifications at the tooth tip. This novel solution opens up prospects for noise emission reduction, trapped volume relief and reduction dynamic loads in gear intermeshing. The knowledge was used to design and build original pumping units. The book's merits are enhanced by numerous drawings and the accessible way in which the theoretical knowledge is presented.