Breast cancer is the most frequent malignant neoplasia worldwide. In emergent countries as Mexico, an increase has been shown in frequency and mortality, unfortunately, most cases in advanced loco-regional stages developed in young women. The success of breast screening in mortality reduction has been observed since 1995 in Western Europe and the United States, where as many as 40% mortality reduction has been achieved. Most countries guidelines recommends an annual or biannual mammography for all women >40 years of age. In 2005, FUCAM, a nonlucrative civil foundation in Mexico join with Mexico City government, initiated the first voluntary mammography screening program for women >40 years of age residing in Mexico City's Federal District. Mammographies were carried out with analogical mammographs in specially designed mobile units and were performed in the area of women's domiciles. This report includes data from the first 96,828 mammographies performed between March 2005 and December 2006. There were 1% of mammographies in Breast Imaging Reporting and Data System 0, 4, or 5 and 208 out of 949 women with abnormal mammographies (27.7%) had breast cancer, a rate of 2.1 per thousand, most of them in situ or stage I (29.4%) or stage II (42.2%) nevertheless 21% of those women with abnormal mammography did not present for further clinical and radiologic evaluation despite being personally notified at their home addresses. The breast cancer rate of Mexican women submitted to screening mammography is lower than in European or North American women. Family history of breast cancer, nulliparity, absence of breast feeding, and increasing age are factors that increase the risk of breast cancer. Most cancers were diagnosed in women's age below 60 years (68.5%) with a mean age of 53.55 corroborating previous data published. It is mandatory to sensitize and educate our population with regard to accepting to visit the Specialized Breast Centers.