Abstract: The purpose of this research was to investigate on the factors affecting market performance of urban housing projects with specific reference to Kilimani area. The focus was on the project developer, the project architect and the project contractor of the housing projects in Kilimani area, Nairobi County. Although there are many factors that may influence market performance of housing projects, this study delimited itself to project cost and project time. The research designs for this study were correlational and the descriptive research designs. The study targeted 167 respondents who were drawn from 56 housing projects which were randomly selected. A questionnaire was used to collect the data and 114 responses were received representing a 68% response rate.