Colour Doppler is a recent and important development among non-invasive diagnostic techniques in cardiology. A series of 500 adults has been studied in order to define the contribution made by colour Doppler to conventional Doppler. After elimination of patients with normal echo Doppler studies, colour Doppler contribution has been considered useful in 51% of the cases and was essential in 13%. Main contributions have been noted in valvular regurgitations, multiple valvular lesions, prosthetic valves and congenital cardiopathies. Colour Doppler appears as an useful, but not as an indispensable complement to conventional Doppler in adult cardiology.