This paper describes the technologies and strategies underlying a state-of-the-art system for automatic handwritten address interpretation. The system is capable of interpreting both street addresses and post office box addresses. The input to the system is a grayscale image of a handwritten address and the goal is to determine the ZIP+4 code corresponding to the destination address on the mail piece. Processing is accomplished through an integrated series of steps involving preprocessing, numeral field recognition (ZIP codes, street numbers, post office box numbers), national postal database retrieval, word and phrase recognition, database record matching, and a decision strategy. In a formal test, this system encoded 38.7 percent of the mail pieces, with an encode error rate of 8.4 percent. Adjusting system parameters designed to tradeoff encode rate for error rate produces an encode rate of 33.8 percent with a 3.9 percent encode error rate.