Background Impairment of the upper limb (UL) is a common consequence of cerebral palsy (CP), and results in difficulties completing daily activities. Methods Literature reviews evaluated UL classification systems and measures of impairment for children with CP. Cross-sectional surveys were mailed to paediatric therapists and families of children with CP to describe the perceived severity of UL problems and current therapy management of such problems. Seven children aged 8-15 years with hemiplegic CP were recruited to a mixed methods study (single subject research design and semi-structured interviews) evaluating the efficacy and feasibility of constraint induced movement therapy (CIMT). Results Five classification systems were recommended for clinical use; two classified function, and three, deformities. Continued use of the Modified Ashworth Scale, manual muscle testing and goniometry when measuring UL impairments in clinical practice was supported. Families and therapists perceived muscle weakness, decreased grip strength, reduced coordination and impaired fine motor function as having a moderate or great impact on the UL in children with the condition. Therapists commonly assessed joint range of motion and muscle strength, however standardised measurement of activity was rare. Current therapy management reflected training received by therapists with neurodevelopmental therapy and positioning being most often reported in managing the UL of children with CP. CIMT resulted in significant improvements in unimanual capacity in four participants, two of whom also significantly improved on UL active range of motion, although UL strength, tone and participation remained largely unchanged. Conclusions This programme of work identified issues regarding assessment and treatment of UL dysfunction in the paediatric CP population. Recommendations regarding UL assessment methods and CIMT, pertinent to clinical practice and research, have stemmed from the completed studies. This thesis has increased understanding of the complexity of UL problems and provides a basis for further research in the area.