Interstitial lung disease in connective tissue disorders is common and causes significant morbidity and mortality. However, the clinical course is highly variable, ranging from indolent to rapidly progressive. Hence, optimal prognostic evaluation is crucial to identify patients at greater risk who should be treated, while avoiding toxicities in those who can be best observed. A pivotal part of this assessment is the quantification of baseline severity and longitudinal disease behavior. In systemic sclerosis-interstitial lung disease, a simple staging system, combining the use of high-resolution computed tomography disease extent and forced vital capacity levels, readily classifies patients into having either mild or extensive disease. The combination of high-resolution computed tomography and forced vital capacity levels provide more powerful prognostic significance than either measurement alone.