The connective tissue diseases are a group of autoimmune mediated disorders characterized by multiorgan damage. High-resolution computed tomography (HRCT) plays an important role in identifying patients with respiratory involvement. Although there is some overlap, typical HRCT appearances are increasingly recognized for each of the major connective tissue diseases and are described in detail in this review (rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, Sjögren syndrome, polymyositis/dermatomyositis, mixed connective tissue disease). The clinical utility of HRCT is discussed with respect to the detection of disease, diagnosis, staging of disease severity, prognostic evaluation, and monitoring of disease progression. The difficult problem of establishing the clinical significance of CT abnormalities is also addressed.