Conclusions in empirical studies of commuting and urban spatial structure depend on the selection of measures for the job-housing relationship. In order to help to develop urban growth strategies based on coherent empirical results, this paper presents a ‘commuting spectrum’ approach as an alternative to existing job–housing relationship measures. With this approach, two hypothetical and extreme commuting possibilities are conceptualized as measures for job–housing relationship and location-choice sets. Simulation in a stylized region and empirical results for Boston and Atlanta indicate that the proposed method can track local and regional aspects of job – housing relationship changes. The revealed association between commuting length and the job–housing relationship is consistent from the perspectives of neighborhood-level comparison, multiyear comparison, and interregion comparison.