In children under the age of 3, the most common solid tumours are brain tumors. Treatment for many of these patients includes surgery, chemotherapy and rarely radiation therapy. Many clinical trials have been performed in an attempt to establish the best treatment for these patients. Patients enrolled on clinical trials contribute to the establishment of the best therapy. We performed a national survey of all children less than the age of three with brain tumours and examined the contribution these patients made to clinical trials. A data bank was established using data collected from Canadian pediatric oncology centers on children less than age 3 diagnosed with brain tumours between 1990 and 2005. Data were collected on the use of adjunctive treatment after surgery, treatment on a protocol, reasons patients were not registered on a protocol, and reasons for discontinuation of therapy. From the 579 cases in the data bank, 302 (52%) patients were treated with further therapy after surgery. The use of further therapy after surgery was significantly higher in patients with cerebellar and brain stem tumors, patients who were over 1 year of age, patients with ependymal and embryonal tumors, and patients with high grade malignant tumors. Only 62 (21%) patients were enrolled on a protocol for therapy. No factor was significant for being enrolled on a protocol. Reasons for not being registered on a protocol were mainly that there was no open COG/POG/CCG study or the study was not open at the institution. The therapy was stopped because of completion of the protocol in 50% and because of disease progression in 34%. In Canada, about half of children under the age of 36 months with brain tumors are undergoing therapy following surgery for their malignancy but only a small fraction of them are enrolled on a clinical trial. There needs to be improved availability of clinical trials for these patients so that novel therapies can be evaluated and survival improved.