This document describes the design and implementation of a fingerprint-based identity authentication system. The system uses an improved algorithm to extract minutiae features from fingerprints faster and more accurately than previous methods. It then employs an alignment-based matching algorithm to find correspondences between input and stored fingerprint templates without exhaustive search. Experimental results on standard fingerprint databases show the system can achieve good performance and satisfy response time requirements for authentication, taking about 1.4 seconds on average. The system provides a means of positive identity verification through fingerprint biometrics with a very high level of accuracy.