The book deals with problems of rheology of solid deformable bodies covering various aspects such as creep, relaxation of tensile stresses and long-term strength. Theories of soil creep have been reviewed and rheological processes occurring in them under natural conditions have been discussed. Laboratory set ups and techniques to determine instantaneous and creep strains in clayey soils have been described. The effect of residual pore pressure and lateral pressure on volumetric and shear strains has been studied and the relation between volumetric and shear strains has been described with particular reference to long-term shear strength of clayey soils, etc. The book should be useful to students of civil engineering and geological sciences.