The revised “Ministerial Ordinance on Good Post-marketing Study Practice for Drugs” (No. 171, Ministry of Health, Labour and Welfare [MHLW], dated December 20, 2004) (hereinafter referred to as “GPSP”) will be implemented in April 2018. It clearly defines “post-marketing database study”, marketing authorization holders requiring to conduct more efficient and effective studies after drug marketing with more suitable and scientific methods than before. Therefore, basic policy for consideration to develop a post-marketing study1 plan is hereby released.