The presence of heated circumstellar dust around WC type Wolf-Rayet stars is reviewed in terms of the episodic or persistent condensation of carbon grains in their stellar winds. At present, 19 WC stars are known to form dust persistently and 7 episodically. Infrared spectroscopy suggests that the grains are amorphous rather than graphitic carbon. The properties of the stars which make dust episodically are reviewed in terms of processes in colliding winds in WR binary systems and the possible applicability of these processes to the stars which make dust persistently in examined.