Waterkeyn was the economic director of Fabrimetal (now Agoria), a federation of metallurgical companies when in 1954 he was asked to design a building for the 1958 World Expo that would symbolize Belgian engineering skills.
Waterkeyn owned the copyrights of all reproductions of the Atomium until he passed it over to the organisation owning the original building around the years 2000. He was chairman of the board of the Atomium until 2002, when his son took over. He died in Brussels in 2005. After his death, the top sphere was named after him.