Musculoskeletal ultrasound (MSUS) is rapidly becoming a standard part of many rheumatologists' daily clinical practice. MSUS is safe, increasingly widely available, relatively low cost, non-invasive, and hence very acceptable to the patient. Current problems with availability of training, mentoring, and accreditation procedures need to be overcome for MSUS to reach its full potential for rheumatologists. MSUS is capable of improving clinical diagnosis and the accuracy of intervention. MSUS is more sensitive than clinical examination in the detection of synovitis and effusion and is capable of rapid targeted assessment of widely spaced joints coupled with clinical correlation. MSUS has advantages over other imaging modalities; the ability to display dynamic real-time movement makes it the imaging modality of choice for tendon problems. It is significantly more sensitive than plain radiology in the demonstration of early erosive changes, and although its sensitivity is less than that of MRI for the detection of erosions it is far more practical, timely, and available. The combination of sensitivity in detection of synovitis, tenosynovitis, and erosions makes it an ideal imaging modality in the context of an early arthritis clinic. Power Doppler has been shown to be an effective way of evaluating synovitis and hence is of value in early diagnosis and monitoring of inflammatory arthritides. The accuracy of placement of local injection therapies is enhanced by MSUS, and it significantly increases the diagnostic success rate of aspiration of joints and bursas. The flexibility of ultrasound as a tool for rheumatologists is shown by its application in the assessment of vasculitides, peripheral nerve pathology, salivary glands, and skin lesions.