A modular and reusable packaging system has a plurality of interconnecting pieces. The pieces have a rigid construction and are configured to connect with adjacent pieces to form the walls of the shipping container. The system also has a closure piece having a locking mechanism configured to releasably engage with at least two of the plurality of pieces when the locking mechanism is operated to securely lock the pieces together. Container forming pieces may have tracking devices that can be used to track location and use, for example. The tracking device may be an RFID tag attached to one or more of the plurality of pieces.