Spiros Simitis (Greek: Σπύρος Σημίτης; 19 October 1934 – 18 March 2023) was a Greek-German jurist and a pioneer in the field of data protection.

When the West German government prepared for the 1978 launch of a national equivalent, he was seen by commentators as the obvious choice for the post of Federal Commissioner for Data Protection.

"The state of Bavaria on its own is budgeting no fewer than twenty data-protection staff for the coming year – a telling comparison" ("Allein das Land Bayern sehe für Datenschutz-Aufgaben in seinem eigenen Bereich im kommenden Jahr nicht weniger als zwanzig Bedienstete vor – eine "bezeichnende Relation"").

[11] Around the time he submitted his dissertation Simitis met the Freudian psychoanalyst-scholar Ilse Grubrich at the home of their friend, the sociologist-philosopher Jürgen Habermas and his wife Ute.

The wedding ceremony for Spiros and Ilse Simitis took place on 3 August 1963, following the Greek Orthodox rite which on this occasion, as one impressed academic colleague noted, involved "dancing around the bride and groom with floral wreaths".

[4][13] It was from the start, in his words, a "reaction to the constant refinement and evolution of Information Technology" (als "Reaktion auf eine sich ständig weiterentwickelnde und verfeinernde Informationstechnologie").

[4] In 1975 he took German citizenship, and this opened the way for him to take over as Chief Data Protection Commissioner for the state of Hessen in succession to Willi Birkelbach, although sources make clear that in reality his was the defining contribution from the establishment of the department in 1970.

With the post still unfilled in November 1977, commentators inferred a lack of commitment to data protection on the part of the government which the powerful IG Metall trades union saw as an "alarm signal for every citizen" (ein "Alarmsignal für alle Bürger").

Between 1999 and 2001 he was a member of the strategy commission dealing with further development of the European University Institute (Florence) and in 2001, through a German cabinet resolution, he joined the National Ethics Council ("Nationaler Ethikrat"), chairing it till 2005.