In this work the authors use a huge, unique data set of about 380,000 firms in Japan during the 2007–2010 period. To grasp the entirety of this enormous data set, which is tantamount to a picture of all firms currently operating in Japan, this brief summarizes descriptive statistics and conducts univariate analyses of the data. Also provided is the legal background of trade credit practice in Japan from the “law and economics” perspective. In this manner, the book furnishes vital information that can be used as a reference for future theoretical and empirical analyses of trade credit and interfirm relationships.