Bonjour Tristesse, Multifamily residential building in Schlesisches Tor, Kreuzberg, Germany.

Bonjour Tristesse is a seven-story residential building on Schlesische Strasse in Kreuzberg featuring a distinctive curved facade with a regular window pattern. The ground floor holds commercial spaces while the six upper levels contain 46 residential units accessed through a central circulation system.

Built in 1982/1983 to close a war gap in the street's old buildings, the house was Siza Vieira's first completed project outside Portugal and a main work of the IBA 87. The original plan of four flats per floor with four staircases was cut for cost reasons; today two staircases serve 46 flats on six floors. The first owner, Kleistpark Hausverwaltung GmbH, went insolvent in 1986.

The name was painted by unknown hands in 1984 on the gable before the scaffolding came down, echoing Françoise Sagan's 1954 novel and its 1958 film. It may mock the uniform window spacing; the red slogan "BITTE LƎBN" has appeared on the house since 2012.

The building sits on a busy street with good access to public transport and nearby shops. As an active residential community, it is visible from outside but residents' privacy should be respected.

The name was not given by the architect: in 1984, before the scaffolding came down, unknown people painted "Bonjour Tristesse" on the corner building's gable, echoing Françoise Sagan's 1954 novel and its 1958 film. Since 2012 the red lettering "BITTE LƎBN" with an appended anarchy A has also been visible on the house.