There is a global demand for turkey products and a high value attributed to breast meat from these birds. Breast meat can be considered the most important component of the carcass and consequently it is important to investigate factors that influence breast meat yield (BMY). The BMY trait is influenced by both genetics and the environment at all stages from pre-hatch until the end of the commercial growing period. Additive genetic effects appear to be the primary contributor to BMY, as there is minimal evidence for heterosis or maternal inheritance. The genetic potential for BMY is affected by sex, strain, and selection pressure within a pure line and this affects both muscle morphology and yield. For a turkey to fulfil its full genetic potential for BMY, optimal husbandry and management is required. Nutrition is an important component of production efficiency, although turkeys may be able to tolerate a reduction in dietary protein levels without a negative response in BMY, provided that the levels of all other nutrients are sufficient to meet metabolic needs. Housing conditions, such as barn temperature and lighting, also influence production efficiency. Cooler temperatures increase both weight gain and BMY, relative to a warmer rearing environment. Further, a light cycling programme with a daily set light and dark schedule is associated with higher BMY values compared to frequently alternating light and dark periods throughout the day in an intermittent lighting regime. Due to the influence of both genetics and the environment on BMY, maximisation of yield requires optimum management by all segments of the turkey production industry from the primary breeder through to the commercial grower.