Abstract: Breast cancer is the most common cancer in women worldwide and its incidence is increasing in most countries. Nurses involved in breast cancer care have an impact on early detection of breast cancer, treatment, and symptom management, and they serve as advocates for women with the disease. In many countries nurses are far more numerous than physicians, and nurses are in an ideal position to influence breast cancer care. The International Society of Nurses in Cancer Care (ISNCC) is an organization representing more than 50,000 oncology nurses in 25 countries. The society provides a communication network for national and regional cancer nursing societies and communication on developments in cancer nursing to nurses working in countries where a national cancer nursing group does not exist. The society also acts as a resource for nurses in practice, education, research, and management, and it serves as a link for other international, regional, national, and local organizations in promoting collaboration to achieve ISNCC's goals. In collaboration with the Susan G. Komen Breast Cancer Foundation, the society developed a 2-day “train-the-trainer” workshop for a selected group of cancer nurses from around the world. The workshop includes didactic presentations, skills instruction, and demonstrations that cover the continuum of breast cancer care. Participants have represented the countries of Brazil, Colombia, China, Italy, Spain, Portugal, Turkey, Pakistan, Australia, Germany, South Africa, Greece, and India. They have subsequently developed educational programs for nurses and the public in their countries, started support groups, published educational materials on breast cancer, and participated in political activities. These advances indicate that despite challenges such as nursing shortages and a lack of resources, cancer nurses are making a difference internationally.