Konstantin Alexander Wecker (born in Munich 01.06.47) is a German singer/songwriter with piano as his main instrument, widely known for his political engagement. He rose to fame in the seventies, with "Willy" (on the album "Genug ist nicht genug" ["enough is not enough"] in 1977) as his first big hit. He has released more than 40 albums, tours extensively, also with Hannes Wader, and also enjoys a carreer as actor (infamous for the sexfilms of the seventies), author (often self-biographical in character) and composer of film-music and musicals. A planned concert in Halberstadt with strom & wasser in March 2006 under the parole "Nazis raus aus dieser Stadt" was cancelled after threaths from the far right (NPD) was cancelled, but was later turned into an Open Air with the same slogan. Wecker is also well known for his drug problems, which led him to jail for a short period of time, a theme that can also be followed in his songs and his books (books: "Ketzerbriefen eines Suechtigen", "Uferlos").

Many of Wecker's songs have lyrics written in the Bavarian dialect and musically he fuses the traditional singer/songwriter ways with jazz and other elements, especially in the years between 1986 and 1993.

Wecker is a member of the international Attac-movement, a pacifist and leftist movement for a more equal world order. He has thus opened a website of his own: Politik hinter den Schlagzeilen (politics behind the headlines). He also writes diary entries of political and trivial nature on his own website.