Since the 1960s, Raetz has created numerous works, including more than 30,000 drawings.[2] His work focused on drawings and paintings in the 1960s and 1970s, and continued with sculptures in the 1980s and 1990s, beginning with the sculpture Der Kopf in the Merian Park in Basel (1984). The principal topic of his work is the nature of perception. His works do not focus on what they portray, but on how they are perceived.