Originally, submetering was designed to be the instrument that would register the energy use of separate tenants or departments, located in a facility, so that each individual entity could be fairly billed or accounted for. Its flexibility and ease of installation made submetering a valuable choice for designers, engineers, and property managers who required accurate billing data. Fast forward to today and we find that submetering is no longer just a tool for billing, but has become the "Swiss Army Knife" of energy monitoring. And, it is not just for electrical energy. Submetering now can account for practically all forms of energy and utilities used in residential, commercial, and industrial facilities. With multiple choices in communication media it gives the user the enhanced flexibility to place the data where it is needed and most effective. Remote reading allows multiple locations to be addressed from a central point and numerous protocol choices will provide the correct interface needed for data acquisition by Building Automation Systems. This presentation will discuss the application of submetering to provide the user with valuable and actionable data on energy usage and how it can be utilized most effectively for continuous commissioning and sustainability. Its diversity will be explored and how thinking "outside of the box" can provide enhanced benefits. It will also discuss present and future mandates that require reporting of energy usage and show how to determine the building's carbon footprint.