Starting from 2021, public subsidies for fertility preservation for CAYA cancer patients have been initiated, and from 2022, there is also public support for assisted reproductive technology(ART)after cancer treatment. On the other hand, regarding fertility preservation therapy, it's not universally beneficial for all cancer patients, and evidence regarding its outcomes and safety from both reproductive medicine and the perspective of the primary condition's treatment is still insufficient. As a result, the"public subsidy system"is being implemented as being coupling with to build evidence through close collaboration between the primary disease treatment and reproductive medical care, focusing on providing information and decision- making support. In response to these developments, the 4th Basic Plan for Promoting Cancer Control and the criteria for designating cancer care collaborative hospitals, among other things, mention the necessity of establishing regional networks for cancer and reproductive medical care and the need to participate in such networks. In this article, we discuss the fundamentals of cancer and reproductive medical care, along with the challenges they present. We emphasize the importance of transitioning from information provision to decision-making support and delve into the current status and issues surrounding the establishment of cancer and reproductive medical care networks. Furthermore, we address the efforts of the Japan Society of Cancer and Reproductive Medicine in resolving these issues and advancing the field.