In principle, the London Zoo was open only to Fellows of the Zoological Society, their families and friends. This policy remained unchanged during the first two decades of the zoo's history. In practice, however, the zoo was accessible even to those who were not acquainted with Fellows. The society carefully regulated its complex admission system, but the illegal entry of those described by the society as ‘improper characters’ was common. There was also a continuing tension between the society's attempts to expel strangers and the growing demand for open access to the zoo. As a result, the question of access arose not only with regard to the London Zoo, but also other public institutions involved in the arts and sciences.