Mammary gland biology is driven by an interest both in the biology of the normal gland and in breast disease. The 2012 GRC Mammary Gland Biology meeting will concentrate on how on understanding normal breast biology drives our understanding of breast pathophysiology. Scientific sessions will focus on cutting edge research directed at the basics of mammary gland biology - the developmental cycle of proliferation, differentiation, lactation and involution. Speakers will also examine how our improving knowledge in these areas is driving a better understanding of breast cancer biology. The conference will include leaders in the field as invited speakers as well as selecting speakers for short talks from submitted abstracts. The 2012 GRC will be preceded by the first Mammary Gland Gordon Research Seminar and post-graduate students and junior post-docs are encouraged to apply for both meetings. The Mammary Gland Biology GRC has a tradition of good interaction across all levels of seniority, from the newest student to the most senior professor, and we look forward to continuing that at Il Ciocco in 2012.