Background Medical treatment under workers’ compensation represents just a miniscule portion (about 3 percent) of total medical costs in the US Furthermore, legislation and rules are determined autonomously by each state. Worker’ comp medical care, and the outcomes of that care, in each state theoretically can represent a microcosm of what could be achieved in an entire country. Impact of Evidence-based Treatment Guidelines: A trend began in 2003, starting with California, for states to consider adopting Evidence-Based Treatment Guidelines as a mechanism to insure timely and quality care for injured workers by following the least invasive, most-effective treatments today’s science has to offer. Bi-products to the effective implementation of EBTG, include earlier return to work, better outcomes resulting in reduced indemnity costs, less friction in the system (providers know what treatments are authorised and will be paid for), fewer episodes of over-utilisation of services, and decreased medical costs, benefiting employers, insurers, providers and business. Outcomes where true EBTG have been implemented: Ohio adopted EBTG in 2003. A Pilot conducted in 2005 showed a decrease in medical costs by 64%, lost days by 69% and treatment delays by 77%. Texas adopted EBTG in 2006; Total costs have declined by 50%, patients are recovering more quickly, more providers are willing to treat these patients, opioid abuses have declined and many states are looking to adopt this model. Other state outcomes and essential elements needed in an EBTG will be discussed.