Plain film radiography is the most widely used imaging technique for diagnosing and monitoring the progression of chronic inflammatory and degenerative joint diseases. Advanced imaging techniques that are better suited for detecting soft-tissue inflammation are available, but they are more costly and some of them may expose the patient to higher doses of radiation. Plain film radiographs are inexpensive, easy to generate, can be compared with baseline and prospective films, and provide a permanent, reproducible record. Radiographs can easily detect the features that are specific to various rheumatological disorders, and serial radiography can be used to assess response to therapy by measuring erosions, joint space narrowing, and other disease-specific features. This chapter discusses the use of radiography for diagnosing and differentiating various rheumatic joint diseases, specifically rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis and osteoarthritis. The most frequently used scoring systems that are used to assess and monitor the severity and progression of these disorders are briefly described.