An accurate automatic personal identification is critical to a wide range of application domains such as access control, electronic commerce, and welfare benefits disbursement. Traditional personal identification methods (e.g., passwords, and PIN) suffer from a number of drawbacks and are unable to positively identify a person. Biometrics refers to automatic identification of an individual based on her distinct physiological and/or behavioral traits. While biometrics is not an identification panacea, it is beginning to provide very powerful tools for a variety of new applications (e.g., cellular phones, smart cards and international border control) requiring positive identification. This paper attempts to summarize important research issues in biometrics.