This book is essentially made up of the lecture notes delivered by seven authors at the International Centre for Mechanical Sciences in Udine in June 1979. It attempts to provide an up-to-date and concise summary of the authors' understanding of micropolar materials. Both asymmetric elasticity and fluids are covered. The chapters range from the discussion of micropolar molecular models to the analysis of structure models, from linear to nonlinear theories and from electromagnetic, thermal, viscous effects to lattice defects. The subjects are treated from both theoretical and experimental points of view. Students with physics, mathematics and mechanical backgrounds as well as professionals will find this treatise useful for study and reference.