Musculoskeletal ultrasonography of the rheumatologist can be useful as a supplement to physical diagnostic assessment or as an aid to diagnostic puncture or therapeutic injection. The essence of musculoskeletal ultrasonography includes visualisation of joints and periarticular structures, muscles, tendons, tendon-sheets and insertions. With ultrasound, punctures, biopsies, and injections can be performed more precisely. A specific ultrasound technique is (color and power) doppler; three-dimensional ultrasonography is a promising new imaging modality. The learning curve of musculoskeletal ultrasonography differs according to indication. Data regarding the validity, reproducibility, sensivity and specificity of ultrasonographic findings are scarce. Further development of guidelines for the use and indications of musculoskeletal ultrasonography is warranted.