The Bureau served as the cabinet or executive committee of the Conservative Delegation. The exact structure of the Bureau varied, but it was typically comprised of the Delegation's leadership and officer roles, plus additional elected members. The principal function of the Bureau was to determine the business to be considered at meetings of the whole Delegation. The Bureau also considered staffing, administrative and financial arrangements, in addition to sensitive political matters.

Prior to May 1992 the Bureau was constituted as the Bureau of the European Democratic Group as a whole, including MEPs from the other national delegations.

From May 1992 onwards, the Delegation Bureau was constituted as the Bureau of the British Section of the Group of the European People's Party (EPP). This setup was retained during the Delegation's subsequent membership of the Group of the European People's Party and European Democrats (EPP-ED), and the European Conservatives and Reformists (ECR) Group. A separate Group-level Bureau, with representatives from multiple national delegations, also existed for each of these three Groups.

The Bureau of the Conservative Delegation should not be confused with the Bureau of the European Parliament (often meeting as the Enlarged Bureau), which is a separate, unrelated body.