The Capacity Design Method forms the basis of several seismic design codes. This design philosophy allows plastic deformations in order to decrease seismic demands in structures. However, these plastic deformations must be localized in certain zones where ductility requirements can be documented in order to ensure the assumed mechanism. Furthermore, according to Eurocode 2 it is allowed, within certain limits, to utilise moment redistributions in continuous concrete beams at the ultimate limit state. To ensure that full moment redistribution is possible it is important to have knowledge on the rotational capacity of the plastic hinges. The documentation of ductility can be a difficult task as modelling of rotational capacity in plastic hinges of frames is not fully developed. On the basis of the Theory of Plasticity a model is developed to determine rotational capacity in plastic hinges in linear reinforced concrete elements. The model is taking several important parameters into account. Empirical values is avoided which is considered an advantage compared to previous models. Furthermore, the model includes force variations in the reinforcement due to moment distributions and shear as well as the effect of shear cracking on the length of the plastic zone.