A multiparty biometric-based access control might be desirable, or even required, in some applications. That is, a group of individuals might have to present valid readings of biometrics parameters in order to gain access to a system or application in order to receive authorization to use a particular resource. Such multiparty schemes can often provide greater protection. This paper presents several techniques for multiparty biometric-based authentication. It also shows a technique for biometric substitution which allows different biometrics to be used concurrently or substituted over time.