To determine whether a nurse-led breast screening educational program in the workplace improved the breast screening practices and attitudes of women. Worksites are potentially cost-effective and convenient for breast cancer screening education due to their ability to educate several women at one time. This was a collaborative study between industry, university and health services in Australia and Thailand. This was a pre post test group comparative design. Three worksites in Australia and three in Thailand were assigned to one of three groups: treatment (group education), pamphlet only, or control. All groups were assessed pre-education and again 3 months post-education on breast screening attitudes and practices using a mail-out self-report questionnaire. Women were significantly more likely to practice breast self-examination (BSE) following group education, and were more confident in their ability to detect a breast lump. There was a significant increase in breast screening discussion on the workplace for the Thai group following the group education program. An increase of 25% more women saw having a mammography as a priority. The Thai women had less access to free mammographic screening. They also had more negative attitudes and poorer knowledge regarding BSE and physical breast examination (PBE) than the Australian group, with the education program having a more positive impact on them than the Australian group. Relative breast screening attitudes and practices for the treatment, pamphlet and control groups are also presented. This study provides educators and health promotion professionals with further information on the beliefs and practices of women working in both Australian and Thai industries about breast screening. Education programs such as this one can have a positive impact on attitudes and practices including increased likelihood and confidence in practising BSE, promoting women to have a PBE, and promoting discussion of breast screening at the workplace. The findings suggest that Australian women have greater opportunities to ensure their breast health than Thai women, and that there may be a greater need for programs such as this in countries such as Thailand.