In 1989, pilot breast screening and assessment services were established in NSW at Central Sydney and in the Hunter region, and in other states of Australia as part of a national breast screening initiative. Following this pilot phase of the Program, in 1991 a decision was made to establish the National Mammographic Screening Program, later known as BreastScreen Australia, as a jointly funded Commonwealth - State Program.

The NSW Mammographic Screening Program was formally established by the NSW Department of Health in June 1992 with Program Management vested under a Performance and Funding Agreement with the NSW Cancer Council. In September 1996, the state management of BreastScreen NSW on behalf of the NSW Department of Health was transferred to Western Sydney Area Health Service WSAHS. In July 1999, a joint management committee was formed for the breast and cervical cancer screening Programs in NSW under the umbrella of the Women's Cancer Screening Programs at WSAHS.

The period July 1991 to June 1995 saw BreastScreen NSW expand to a network of 10 Screening and Assessment Services with 51 screening units. This included a contract with the ACT Community Care for screening women in the South-East of the state through BreastScreen ACT. These ten Screening and Assessment Services provide breast screening and assessment across the seventeen Area Health Services in NSW. Since 1995, the Program has focussed on increasing screening participation by women aged 50 - 69 and expanding services in line with population growth. There are now over 200 BreastScreen locations in NSW, including a combination of fixed and mobile services.