Crossbreeding between different breeds of rabbits (local and exotic) under the Egyptian conditions was generally associated with an improvement in most economic traits in rabbits (e.g. litter size and weight, mortality, litter gain, mean young weight per litter, postweaning body weights and gain, etc...). Heterotic effects on litter traits (e.g. litter size & litter weight) were more pronounced at weaning rather than at birth. Breed of doe was more important than breed of buck in influencing crossbred litters. Local breeds (e.g. Giza White & Baladi Red and White) are superior in prenatal abilities while foreign breeds (e.g. New Zealand White, Californian, Bouscat, etc ...) are superior in post natal maternal abilities. Double crossbred litters or rabbits (i.e. crossbred litters or rabbits produced by crossbred dams) were superior in performance than those of single crossbreds (i.e. crossbred litters or rabbits produced by purebred dams) or purebreds. This encourages the commercial rabbit breeders in Etgoy pt use crossbred dams insteado f pure ones. Crossbred litters and rabbits resulting from matinbgu cks of local breeds (e.g. Giza White, Baladi Red and White) with does of exotic breeds (e.g., New Zealand White, Californian, Chinchilla, etc ...) showed considerable positive heterosis for most economic traits in rabbits, while crossbred litters and rabbits mothered by does of local breeds showed negative heterosis in most cases.