Biometrics are used to verify and automatically identify a person based on their physiological or behavioral characteristics. Various modalities have been proposed, researched, and utilized as biometrics: they can be divided into 1) physiological biometrics, such as fingerprints, DNA, iris measurements, as well as vein and face characteristics, and 2) behavioral biometrics, such as gait and handwriting. Biometrics have mainly been used in two ways. One is called one-to-one verification, which verifies an individualʼs identity. The other is called one-to-N identification, which finds the most approximate individual out of a prepared database. The former, verification, uses biometrics as a surrogate for the tools currently used to confirm identity, such as ID cards, keys, or passwords. The latter, identification, is used for criminal investigation, prevention of shoplifting, as well as by customer service. The performance of biometrics is usually defined by the methodʼs false acceptance rate (FAR) and false rejection rate (FRR) using a predetermined threshold. Both FAR and FRR are dependent on the given threshold level, which means there is a trade-off between them. If one is lowered, the other increases. Among biometrics, facial recognition technology based on computer vision and pattern recognition has progressed dramatically with the introduction of big data and machine learning, which enable us not only to know who an individual is and to estimate their age and sex, but also to infer emotions and intent from facial expressions and to diagnose potential disorders based on facial images. Some of those functions have already been deployed in the real world. The field of biometrics, like other emerging technologies, brings us new experiences, while it has been pointed out that it can also bring about emerging risks depending on how the biometrics are used. In the face of rapid progress and the prevalence of biometrics, particularly facial recognition technology, many countries have started or continued discussions regarding to what extent existing laws and regulations can apply, how to regulate biometrics, and what the best governance framework is. In the United States, law enforcement organizations have already applied biometrics to border management in the absence of comprehensive federal laws regulating acquisition and usage of biometrics. In England and Wales, the police department has repeatedly run trials of live facial scans using surveillance cameras at large events, such as festivals and concerts. Scotland is in the process of establishing a governance framework for facial recognition technology. In Australia, the federal and state governments have agreed to share their facial photo databases. In the EU, biometrics have not been prevalent compared to their usage in other developed countries, since biometric data have been explicitly designated as sensitive data in the General Data Protection Regulation. India has begun to incorporate biometrics into the largest national ID system in the world. In the context of international aid, UN agencies promote the use of biometrics, while some nongovernmental organizations have decided not to use them for fear of data leaks. In Japan, biometric data are classified as “individual identification codes,” one form of personal information in the Amended Act on the Protection of Personal Information. Those who work with biometric data must carry out the obligations specified in the law for “Personal Information-Handling Business Operators.” In addition to complying with the law, business and academic organizations have already embarked on an effort to prepare voluntary guidelines in order to protect privacy and prevent possible chilling effects. 〔The table of contents and the summary in English are contained in the following document. https://doi.org/10.11501/11257102〕