Vasomotion is the rhythmic alteration of vascular diameter that occurs, in many if not all, arterial vessels. In vivo, it results in the oscillation of microvascular perfusion (flowmotion) in many tissues. Although it has been recognised for a long time that flowmotion, theoretically, enables greater delivery of nutrients it has only recently become apparent that alterations in flowmotion have other important physiological roles. Alterations in the patterns of flowmotion may be a major underlying mechanism linking endothelial dysfunction to cardiovascular disease states such as insulin resistance and hypertension. Vasomotion can be measured in intact tissues and isolated vessels with microscopy, but microvascular flowmotion in vivo is harder to observe and quantitate. In humans, intravital videomicroscopy can be used to observe the nailfold microcirculation but has limited use in other tissues. Laser Doppler Flowmetry (LDF) using skin surface probes has been the most commonly used technique to observe microvascular flowmotion in humans. The LDF flux signal, which is a quantity proportional to the product of the average speed of blood cells and their number can be analysed to determine the microvascular flow rhythms. Application of Fourier or wavelet analysis to LDF signals from human skin has revealed 5 distinct peaks in the frequency domain between 0.009-1.6Hz. These peaks have been associated with the following activities: endothelial: 0.009-0.2Hz (~1 cycle/100s); neurogenic: 0.02-0.06Hz (~1 cycle/25s); myogenic: 0.06-0.15Hz (~ cycle/10s); respiratory: 0.15-0.4Hz (~1 cycle/5s); cardiac: 0.4-3Hz (~1 cycle/s). LDF can also be used to measure flowmotion in other tissues but this involves invasive needle probes to be inserted into the tissue of interest with the concomitant risk of disrupting normal blood flow patterns and thus has limited use to mostly skin. A method based on contrast-enhanced ultrasound (CEU) using gas-filled microbubbles is potentially a new minimally-invasive technique to assess microvascular flowmotion in a number of tissues. Developments in ultrasound technology have allowed real-time CEU measurement of microvascular volume that like LDF can be analysed to determine microvascular flowmotion rhythms. Application of these two techniques (LDF and CEU) will allow microvascular flowmotion to be investigated in a number of pathological states and provide a new understanding of the origin and consequences of cardiovascular diseases.