Japanese investigators have conducted clinical trials with little public funding for a long time. The Japan Clinical Oncology Group (JCOG) works only with public funding, and other clinical trial groups, such as the West Japan Oncology Group (WJOG), the Japanese Gynecologic Oncology Group (JGOG), and the Japan Adult Leukemia Study Group (JALSG), operate mostly from pharmaceutical company donations. Furthermore, most investigators are not remunerated for clinical trials; Japanese hospital directors have spent more money to increase medical service fees than to help clinical investigators. Japanese people are aware of the importance of evidence-based medicine in clinical practice. Thus, investigators must conduct many clinical trials to standardize therapy for which high-quality data are needed, but higher quality implies higher costs. When considering the infrastructure of investigator-initiated clinical trials, the physical infrastructure for daily practice (hospital wards, diagnostic units, space for drug storage, etc.) has already been provided. However, human resources are limited to those involved in daily practice. Clinical research coordinators and clerical assistants are vital to clinical trials, but they are temporary workers with relatively low salaries and inadequate benefits; their salaries depend on investigators' research funding, but investigators must manage without public funding. In addition, investigators need to take courses on research ethics, biostatistics, the latest treatments under development, and more, but they lack the time. As clinical investigators, our mission is to conduct good clinical trials; therefore, we always follow more than 20 investigator-initiated clinical trials, including multicenter trials conducted by JCOG or WJOG. We plan to review the existing infrastructure of investigator-initiated clinical trials at our institute, Osaka City General Hospital, a public regional hospital, to identify current problems.