There is considerable evidence from epidemiological studies to support a positive association between alcohol intake and risk for breast cancer. Yet, experimental evidence has provided less convincing evidence to support this relationship, although much less attention has been focused on elucidating the effect of ethanol on breast carcinogenesis in animal models. Although the number of reports are limited, information on the effect of ethanol on mammary carcinogenesis in spontaneous, chemically induced and metastatic models has been published. In addition, a small number of reports provide insights into an influence of ethanol on the physiological processes associated with the initiation, promotion, and progression stages of breast carcinogenesis in animals, as well as on the growth of human breast cancer cells. This information from the literature is summarized, and specific recommendations put forth so that greater progress can be made in this controversial and complex research area.