Much of the dark meat from U.S. broilers continues to be exported to other countries because of local consumers’ long-standing and strong preference for white breast meat. In this review we will discuss what causes meat colour differences and how environmental and genetic factors influence the colour of poultry meat. It is well documented that the darker colour of leg/thigh meat is due to the larger amount of myoglobin and haem pigments, as well as a higher pH when compared to breast meat. Slaughtering older birds increases myoglobin content in the meat and selection of breeds for greater breast meat yield may be involved. Using a wheat-based diet tends to lighten the colour of breast meat but has less effect on the thigh meat. Several antimicrobials used in further processing can lead to either bleaching or a reddening of the meat. Changes to colour using chemical or physiological methods are theoretically possible, however may not be great enough to improve consumer acceptability. From a marketing perspective, increased media promotion of dark meat as being equal to white meat in healthiness and superior in flavour may have the greatest effect on increasing sales.