This year, 1988, the Royal Zoological Society “Natura Artis Magistra” (usually abbreviated to “Artis”) is celebrating its 150th anniversary. During all the festivities, hardly any attention has been paid to the fact that its library was also founded in 1838. In order to rectify this, this editorial briefly reviews the history of the Artis Library and its superb collection. It is known that from the very beginning books were donated to the Society; for instance a complete Buffon edition was acquired in the first year of the Society’s existence. Very little has been published on the early history of the Society’s library, although much relevant information can be found in the “Artis” archives (now deposited in the Amsterdam municipal archives).