Bonnier, Sweden's largest publishing house, has added an extension to their post-war offices in Stockholm. The new building is quite straightforward - a transparent glass and steel structure that sleekly follows the perimeter of what used to be one of the office's garden terraces. This generates the building's most conspicuous feature - the flat iron form. The Bonniers have been keen collectors for as long as they have been publishers. So when they announced to house a gallery in the new extension, many expected it to be a display of their own collection. However, this is not the case. The focus is rather seriously and promisingly on contemporary art. A fully glazed building does entail some obvious challenges, such as how to deal with the sun. The aluminium louvres on the south fašade facing the railway track, completely transform the building when the sun shines. It changes from a delicate glass structure into a Potemkin-like wedge, which is not necessarily a bad thing.