<p>The current coverage rate of sewerage systems in Japan exceeds 80%. The appropriate treatment and recycling of sewage sludge are becoming increasingly emphasized. Historically, sludge was disposed at sea or used as an organic fertilizer. However, given the spread of sewerage systems and lifestyle changes since the 1960s, the amount of sludge has increased rapidly, rendering it difficult to find suitable disposal sites. Consequently, efforts have been made to reduce the volume of sludge and to recycle it. The 1996 revision of the Sewerage Act made it compulsory to reduce the sludge volume, leading to the expansion of recycling. In 2015, the conversion of sludge into fuel and fertilizer became a government policy, and the doubling of sludge use as fertilizer by 2030 was mandated. To allow the conversion of sludge into fertilizer, new safety standards for heavy metals and other substances have been introduced, as well as new standards for “bacterial phosphate fertilizers.” Converting sludge into energy in the form of biogas and solid fuel is being promoted to reduce greenhouse gases and establish a sound material cycle society. The Ministry of Land, Infrastructure, Transport, and Tourism (MLIT) is seeking to expand resource recycling by considering regional characteristics. The MLIT offers financial support for projects that demonstrate new technologies, reducing environmental burden and promoting the effective use of resources.</p>