Keijo Petäjä (1919–1988) had a shared office with Viljo Revell from 1949 to 1952. During those years, they designed the Hotel Palace together. He established a shared office with his wife Marja Petäjä (1923–) in 1950, after they won the architecture competition of the Central Finland vocational school. Marja and Keijo Petäjä designed among other projects, their own home and office premises to Lauttasaari, Western Helsinki. Bringing domestic and workspaces together was a common choice for architect couples in the 20th century, to combine work and family life, Aino Marsio-Aalto and Alvar Aalto being pioneers of this choice. One of Marja and Keijo Petäjä’s key works is Lauttasaari Church. Architects Juha Petäjä and Käpy Paavilainen (née Petäjä) are Marja and Keijo Petäjä’s children. After Keijo Petäjä’s death, their son Juha has been running the office, which operates in the same premises since 1957.