This study investigated factors influencing general practitioner (GP) referrals to a tertiary paediatric neurodisability service, including the reasons for referral, the children's characteristics, and the involvement of secondary specialist services in the referral. Fifty general practitioners (GPs) referring consecutively to the Neurodisability Service, Great Ormond Street Hospital for Children, London, were interviewed in a cross-sectional study using a postal questionnaire. The main findings were that two-thirds of the GPs did not contact secondary specialist providers prior to referring. The majority (78%) of GPs were responding to parental concerns in the context of a lack of medical diagnosis in 74% of the children. The main (90%) reason given for referral was for parents seeking a second opinion outside their district network. The findings highlighted the influence of parents over GPs' referrals to tertiary neurodisability, and, in light of this, raised issues for consideration for effective organisation of child disability health services.