The present application provides, in one embodiment, a modular shelf system having spaced apart upright subassemblies that each include a first and second removable support standard recessed within. The system further provides at least one shelf fixture configured to be removably mounted to at least one of the support standards in each of a first and second upright subassemblies selected. The shelf may receive retail product trays via snap-fit fasteners. And, a variably configurable hanger bar may support the modular shelf system.