A computer-implemented system and method is disclosed for inventory management including an inventory machine, a medication tray, and at least one marker. A medication tray includes a plurality of compartments to receive medications and other items, where each compartment is designated as a receptacle for a specific item or type of item. A marker is provided for each item placed in a compartment, and insertion of a medication tray into an inventory machine enables components to scan for markers. The markers are configured to generate identifying data and other data related to an item upon being scanned by an imaging apparatus and processed by a decoder apparatus. The correct/incorrect location of items within a medication tray, among other information, is determined in an automated fashion as part of the computer-implemented inventory management system and method.