Technical Abstract: Production of fruit on first year canes, or primocane-fruiting in caneberries (Rubus L.) has proven to be an important trait, allowing production, particularly for the fresh market, to expand into new geographic areas and non-traditional seasons. While not a new trait, primocane-fruiting black raspberries have received new attention from breeders in recent years. Despite this, relatively little is known about primocane-fruiting in black raspberry because historical sources of the trait have been lost, and little has been written on the subject. Modern sources of primocane-fruiting include seedlings of floricane-fruiting black raspberry cultivars as well as wild black raspberry germplasm. Expression of primocane fruiting in these plants is variable, and further study on the genetic control of primocane fruiting and the effects of environmental influences on expression are needed.