Twenty years ago, the Aga Khan Foundation established a branch office in Lisbon, where there is a large Ishmaelite community. In view of the growing numbers of this group of Muslims today, the foundation decided to erect a prayer hall with a cultural, pedagogic and social centre. The winning competition entry incorporates Islamic, Iberian and Indian elements and integrates the mosque in a complex of buildings with secular uses. The internal courtyards, which form part of a flowing sequence of spaces and are an important feature of the centre, are characteristic of both Iberian architecture and Islamic mosque construction. Three smaller courts serve to illuminate the teaching areas and the foundation’s rooms on the upper floor, while the public uses on the ground floor are grouped around three main courtyards of different character. The entrance court, with a garden and running water, is of Iranian inspiration and is a place of calm in the hectic urban surroundings. There is also a “community courtyard” between the hall and the multi-purpose space. The arcaded prayer court, entered through a gateway, forms an extension of the prayer hall and the climax of this sequence of open spaces.