Persons with Gross Motor Function Classification System (GMFCS) levels IV and V are considered as severe cerebral palsy (CP) and are non-ambulatory. These persons are at a higher risk of complications such as hip displacement (sub-luxation or dislocation), spinopelvic deformities, musculoskeletal pain, low bone mineral density and low energy fracture. The recommended management strategy at present for this group is wheelchairaided mobility, with which none of these complications can be prevented. There is a strong need to evaluate alternative methods of treatment that can allow assisted ambulation in persons with severe CP. The role of Single Event Multilevel Lever Arm Restoration and AntiSpasticity Surgery (SEMLARASS) and protocol-based active rehabilitation on gross motor function and ambulation of non-ambulatory persons with CP at GMFCS levels IV and V is examined. Active rehabilitation involves making the person with severe CP active through most of the waking hours and participating actively in the rehabilitation. A wellplanned and executed SEMLARASS, followed by intensive, protocol-based, sequenced multidisciplinary active rehabilitation, provides the persons with GMFCS levels IV and V a significant functional improvement in gross motor function and mobility. cognitive, social, behaviour, speech and communication, seizure disorder, respiratory illness and other musculoskeletal disorders [1]. A total of 17 million persons are estimated to have CP worldwide and CP is one of the most common causes of physical disability among children. The prevalence of CP is currently estimated to be 2.11/1000 live births [2] and varies between 1 and 5/1000 live births in different countries. 28% of persons with CP have epilepsy, 58% have difficulties with communication, 42% have visual problems and 23-56% have learning disabilities [3].Clinicians classify patients with CP to describe the specific problem, to predict prognosis and to guide treatment. Classification is based on the change in muscle tone, anatomical region of involvement and severity of the problem. Types of CP according to muscle tone are spastic (hemiplegia, diplegia and quadriplegia based on anatomical region of involvement), ataxic and dyskinetic (dystonia and choreoathetosis). Even though these terms do not have specific reliability among the observers, these terms are helpful for understanding the CP condition [4]. Gross Motor Function Classification System (GMFCS) is another system to classify gross motor function of children and youths with CP on the basis of their self-initiated movement with particular emphasis on sitting, walking and wheeled mobility. Children and youths with GMFCS levels IV and V are non-ambulatory and are considered as severe CP. Persons in GMFCS level IV use wheelchair, either manual or automatic, for transportation and persons in GMFCS level V are highly dependent because of the lack of balance in head, neck and trunk, and will require major assistive devices for physical assistance [5].According to data from North India, 69% of ...