This paper describes the development of a computer program for architects to provide guidance on wind and earthquake vertical lateral load resisting structure. The program, akin to an expert system, is suitable for designing low to medium-rise buildings in New Zealand at a preliminary design stage. Examples of design guides, providing more general lateral load resisting structural information for commonly used structural systems and materials, appropriate to a preliminary design stage, are also presented. Application of the program to the seismic design of a four storey reinforced concrete building is discussed.