This course focuses on elasto-plastic soil models and their use in FE analyses of geotechnical engineering. The first group of models to be considered consists of perfect-plasticity models, e.g. Drucker-Prager, Mohr-Coulomb and the failure model by Lade. In all these models the use of a non-associated flow rule is shown to be essential. The second group of models are isotropic hardening models that involve an expanding yield surface. Advantages and limitations will be given as well as the selection of suitable input parameters from laboratory tests. A special lecture will concentrate on viscous effects in soft soils and another special lecture deals with jointed rock. Applications are shown in tunnelling and foundation engineering.