This thesis is conducted to investigate the relationship between strength andrnductility demand. The base shear and the story displacement ductility were used asrnparameters to establish the relationship and a five story and ten story reinforcedrnconcrete shear frames were used to this end. Eighteen shear frames with differentrncombinations of ductility class and sub-soil class, according to the Ethiopian BuildingrnCode Standard EBCS 8, 1995, were considered. Each model was subjected to one linearrnstatic with EBCS 8, 1995 base shear distribution, two linear response spectrum EBCS 8,rn1995 and EC 8, 2004, two non-linear static and one non-linear time-history analysesrncases using the computer program SAP 2000 Ver.12.rnA range of base shear values were applied on each model to study the post-yieldrndisplacement ductility demands imposed on it. From the analyses results, differentrncurves showing the relationship between the reduced (%) base shear yield strength andrnductility demand were produced. To this effect, the non-linear static or the pushoverrnanalysis method was used as a tool. Two types of non-linear properties were consideredrnfor all the models; the first, material non-linearity following the recommendations byrnFederal Emergency Management Agency FEMA 356 Pre-standard and Commentary forrnSeismic Rehabilitation of Buildings and Applied Technology Council ATC 40 SeismicrnEvaluation and Retrofit of Concrete Buildings and the second Geometric non-linearityrnby implementing the iterative P-D analysis procedure included in SAP 2000 Ver.12.rnThe influence of undermining the design base shear on ductility demand and thernvalidity of permitted reductions by EBCS8, 1995 of design base shear through arnbehavior factor for each ductility class for the five and ten story shear frames wasrnassessed by making use of theses curves. Finally the implementation of the relationshiprnbetween these two important seismic design parameters in the current seismic designrnpractice of Ethiopia was investigated by conducting a case study on an existing buildingrnlocated in Debre Birhan.rnKey words: Base shear yield strength; Ductility demand; Pushover analysis