The inaugural European Network for Breast Development and Cancer (ENBDC) meeting on 'Methods in Mammary Gland Development and Cancer' was held in Weggis, Switzerland last April. The goal was to discuss the details of techniques used to study mammary gland biology and tumourigenesis. Highlights of this meeting included the use of four-colour fluorescence for protein co-localisation in tissue microarrays, genome analysis at single cell resolution, technical issues in the isolation of normal and tumour stem cells, and the use of mouse models and mammary gland transplantations to elucidate gene function in mammary development and to study drug resistance in breast cancer.