Neoadjuvant (primary systemic) treatment is the standard treatment for locally advanced breast cancer and a standard option for primary operable disease. Because of new treatments and new understandings of breast cancer, however, recommendations published in 2003 regarding neoadjuvant treatment for operable disease required updating. Therefore, a second international panel of representatives of a number of breast cancer clinical research groups was convened in September 2004 to update these recommendations. As part of this effort, data published to date were reviewed critically and indications for neoadjuvant treatment were newly defined.