A modular cabinet structure, process, and system are provided, in which a modular cabinet structure comprises a structural frame comprising a first side and a second side, and a first end and a second end opposite the first end, wherein the frame structure comprises a removable frame component at the second end; and a face assembly; wherein the face assembly is fixedly retained within the frame structure when the removable frame component is affixed to the frame structure; and wherein the face assembly is movable in relation the frame structure when the removable frame component is detached from the frame structure. In frame-style embodiments, the face assembly comprises a central panel having a front surface and a back surface, a retaining assembly attached to the back surface of the central panel, and a face frame having a front surface and a rear surface attached to the central panel. In full panel-style embodiments, the face assembly typically comprises a full panel having a front surface and a back surface, and a retaining assembly attached to the back surface of the panel. The modular cabinet structures can be used for cabinet doors and/or cabinet drawers, such that the face assemblies are readily installed and/or replaced.