Over the last decade, there has been a growing body of evidence on the validity of Doppler ultrasound for assessing inflammatory changes in target anatomic structures involved in rheumatic diseases such as joints, tendons, entheses and vessels. The enhanced sensitivity for detecting low-velocity flow in synovium vessels achieved by current Doppler techniques has lead to the incorporation of Doppler US in the assessment of joint and inflammatory enthesis lesions. This review offers an overview of the key aspects of current applications and limitations of Doppler ultrasound in inflammatory rheumatic diseases. The basic principles of Doppler modes, Doppler scanning method, and Doppler artefacts and pitfalls in rheumatology ultrasound are also described.