This paper describes the results of an investigation into the expected seismic performance of reinforced concrete buildings constructed between 1936 and 1975. Typical design and construction features of these buildings are reviewed, including a chronological comparison of post-1935 seismic design levels. Two reinforced concrete frame buildings constructed in the 1950s were the subject of inelastic analysis, and it is found that member shear and poor joint performance tended to govern the ultimate response. An analysis procedure for evaluating the seismic performance characteristics of reinforced concrete frame elements is proposed. Case studies illustrate this method, one of which highlights the adverse influence of highly eccentric building layout.