ABSTRACT: Fixed Functional Appliances was first introduced by Dr. Emil Herbst of Germany in 1909. It has come into practice since 1930s, way back a long history related to its use, method of action and its effectiveness. These appliances transfer their forces to the dentition and underlying basal bone. The resultant orthodontic and orthopedic changes are due to the net muscle forces that are delivered when the mandible shifts its position sagittally and vertically. Correcting class II malocclusion has always challenged an orthodontist owing to the complex and multifactorial aetiology. Age of patient and selection of the appliance plays an important role in the outcome of the treatment. Modifying the growth using functional appliances achieves stable results in class II patients. There are different types of fixed functional appliances available till date. A keen analyses of the patient and adopting the correct appliance helps in better results.