A modular banknote apparatus (1) comprising: a banknote acceptor module (2); a banknote dispenser module (3); at least one banknote storage drum module (4); and a banknote transport module (5); wherein said banknote transport module (5) mechanically and electrically interconnects said at least one banknote storage drum module (4) and said banknote dispenser module (3); and wherein the banknote transport module (5) is configured to provide electronic control of both the banknote dispenser module (4) and the at least one banknote storage drum module (4) in a respective master and slave relationship.