In children with spastic quadriplegia, also described as 'whole body involvement', spasticity can interfere with motor function, contributes to the development of deformities and adversely impacts on care, positioning, and comfort. In this population, spasticity interventions address goals such as improving comfort, reducing pain, easing the burden of carers, slowing the progression of musculoskeletal deformities and perhaps improving function. Children with severe diplegia are distinguished from those with quadriplegia by their ability to ambulate, as well as by a greater emphasis being placed on functional motor goals even though similar treatment modalities are often employed to manage spasticity. The many treatment options currently available include, but are not limited to, botulinum toxin type A, phenol neurolysis, oral medications, intrathecal baclofen, selective dorsal rhizotomy, and orthopaedic surgery. The integration of these treatment modalities can help to optimize the overall care and function for a child with spastic quadriplegia or severe diplegia. However, the development of a management programme is complex and needs to take into account many factors, including age, weight and nutritional status, rate of progression of musculoskeletal deformities, developmental potential, comorbid conditions, current functional status and prognosis, and family and patient treatment goals. Children with marked spasticity are likely to benefit from a combination of interventions, rather than a single treatment modality. Because of these complexities, management should be planned and coordinated by a multidisciplinary team of medical and allied health professionals which recognizes the central role of the family in all decisions. Once the special characteristics of the child with spastic quadriplegia and the various treatment options are understood, outcomes can be maximized.