In 1986 Dr Nittve was appointed Chief Curator at the Moderna Museet in Stockholm. In 1990-95 he served as Founding Director of Rooseum – Center for Contemporary Art in Malmö, Sweden. In July 1995, Dr Nittve became Director of the Louisiana Museum of Modern Art in Humlebaek, Denmark. In the spring of 1998, he was named the first Director of Tate Modern, London. In the end of 2001, after almost four years in the post he moved back to Stockholm to serve as Director of the Moderna Museet. From January 2011 – January 2016, Dr Nittve was the Executive Director of M+ in Hong Kong. In 2016 he established Nittve Information Ltd, based in the mountain resort of Åre, Sweden, acting as an independent writer and advisor to museums and foundations worldwide.