The use of patient data in the real world settings, so-called real world data(RWD), for clinical research is attracting attention worldwide. Therefore, it is essential to know the important points in conducting or interpreting clinical research utilizing RWD. This review describes international trends in RWD utilization research and collection methods. First, representative examples of RWD utilization studies are presented, followed by a discussion of the increasing use of RWD in the future. In particular, the trend of utilizing RWD as an external control group for clinical trials has been increasing in recent years, and I discuss examples of overseas RWD utilization studies. Next, there is a growing trend to utilize RWD for regulatory aspects such as approval applications, and examples of such applications is presented. Finally, methods have been developed to efficiently collect the patient information necessary for clinical cancer research with minimal burden on medical professionals in order to create larger-scale, high-quality RWDs that can be used for a variety of research purposes. This effective methods for collecting RWDs on a larger-scale and of high-quality, as well as global developments, are described.