This book stands as the first comprehensive exploration of the intricate issue of energy poverty in Japan. Unveiling a nuanced exploration, the book breaks new ground by focusing on a unique category of households vulnerable to energy poverty, a revelation grounded in meticulously gathered, up-to-date data. The book not only dissects the fundamental aspects of energy poverty in Japan in detail, providing a comprehensive review of Japanese studies on energy poverty, but also introduces an innovative methodology for assessing vulnerability at the grassroots level.