A plastic–damage model for reinforced concrete frames is developed in this article, based on the classical plastic model and the continuum damage model. The plastic–damage constitutive law is implemented into a beam model for framed structures, in which these are described by elastic beams and columns with two inelastic hinges at their ends. A numerical procedure for predicting the member and global damage in framed structures using the matrix analysis is developed. Additionally, the article introduces a damage index useful in evaluating the state of structural members and a meaningful global damage index for whole structure. The plastic–damage model, together with the member and global damage indices, are adequate for the computation of the limit load of reinforced concrete frames subjected to seismic actions. Examples of applications of the methodology to the non-linear analysis of reinforced concrete framed structures are finally given.