Hasan Khan graduated as an architect from the Architectural Association, London, in 1972. He worked in London, after which he returned to Karachi, Pakistan, to private practice in his own firm UNIT 4, until 1976. He worked in the USA and helped form the Aga Khan Award for Architecture and was its second Convenor in 1980.

He lived in Jakarta, Indonesia between 1980 and 1983, working as a consultant; founder and Editor-in-Chief of Mimar: Architecture in Development, and head of Concept Media Ltd. publishers, Singapore.

He worked for in France from 1984 as Head of Architectural Activities for HH the Aga Khan: helped form the Aga Khan Trust for Culture in Geneva and there was Director of Special Projects, 1991-94, which included architectural, historic preservation and cross-cultural projects.

Hasan joined the Massachusetts Institute of Technology (MIT), as Visiting Associate Professor of Architecture, 1994–2000, and was appointed Distinguished Professor of Architecture and Historic Preservation at Roger Williams University. He has also been Visiting Professor at the University of California at Berkeley.

His current research focuses on contemporary architecture and cities in Asia, mosque buildings, and architectural conservation in Asia and the Middle-East. He lectures widely, and is editor/author of nine books on architecture and has over sixty published articles. He consults on issues related to contemporary Islamic architecture and continues a limited architectural practice.