The aim of this thesis was to develop a decision aid for young patients faced with the decision to have dental treatment with inhalation sedation, intravenous (IV) sedation or general anaesthesia (GA). A series of qualitative interviews were undertaken with patients aged 10-16 years, who had already undergone dental treatment with sedation or GA, and their parents/guardians. The data collected from these interviews were used to inform the content of a draft decision aid, which was presented to a focus group of expert clinicians and to former patients and their parents/guardians in a further series of interviews. Following further revisions, the decision aid was tested with patients who were faced with the decision to undergo dental treatment with inhalation sedation, IV sedation or GA. Patients, aged 10-16 years, and their parents/guardians were recruited from the Liverpool University Dental Hospital and randomly assigned to two groups. Patients assigned to the control group received routine clinical counselling prior to making a treatment decision, whereas patients assigned to the intervention group received routine clinical counselling and the decision aid prior to making a treatment decision. Patients and parents/guardians in both groups received a questionnaire measuring decisional conflict and knowledge. Patients’ questionnaires also included a measure of dental anxiety. Patient attendance throughout the care pathway was also monitored. Significantly higher knowledge was associated with the use of the decision aid when compared to standard care. The decision aid had no significant impact upon measures of anxiety or decisional conflict. Findings suggest that it may not be feasible to deliver the decision aid in secondary care. Further research is required to determine the feasibility of implementing the decision aid in a primary care setting and to explore the impact of the decision aid on attendance, compliance with treatment and participation in the decision-making process.