External Senses, the second volume in the series Medical Physics, focuses on the electrophysiology and biophysics of the receptors as these are common in each species. This book also briefly discusses brain pathways but the topic on synapsing mechanism and brain electrophysiology are covered in the last volume. This volume focuses on the category of senses which respond to external stimuli - taste, smell, touch, hearing, and vision. The results of research presented in this volume, although limited in terms of medical applications because they are not precisely defined, pave the way towards medical treatment in the future. The topics of each chapter focus on broad areas such as: gustation, olfaction, cutaneous sensation, audition, vision, and psychophysics. This book is a helpful tool for all undergraduates, premedical students, and postgraduate students of various scientific disciplines.