Abstract: The impact of developer competency on motor vehicle navigation software quality was investigated, yielding a computing method for software quality, defect density, productivity, and developer competency level. By analyzing the quantitative effect of developer competency on quality of the vehicle navigation system, the computed result can be used to organize the software project development team. Analysis showed a correlation between software quality, defect density, productivity and developer competency level, with an inverse proportional relationship between defect density and developer competency level. A regression equation and matrix of the critical competencies of the developer were also determined.