Eating disorders are serious illnesses with both physical and psychological symptoms. In the case of anorexia nervosa, the evidence suggests the earlier one identifies and treats the illness, the greater the chance of full recovery. In 2010 the New Zealand Ministry of Health provided funding to roll out the evidence based, Family Based Therapy (also known as Maudsley Family Based Therapy [MFBT]), treatment for anorexia nervosa, to specialist eating disorders services and clinicians in child and family services. The main focus of this chapter is the planning behind the implementation and sustainability processes, the evaluation, and the initial outcomes of the implementation of MFBT. Finally, lessons learned and recommendations from the implementation process will be outlined.