Swedish songwriter, born July 7, 1970 in Mariestad.

He co-wrote Lyssna till ditt hjärta, Friends' winning song in the Swedish Melodifestivalen 2001. He also wrote the Danish winning entry in 2010 In a Moment Like This which finished 4th in the Eurovision Song Contest. In total, Sethsson has had twelve songs around Europe in Eurovision, of which two wins and a third place as the main merit.

Has also figured in the dance band genre where he has written for, among others, Lasse Stefanz, Lotta Engberg, Scotts, Black Jack, Larz-Kristerz, Elisas and more. He participated in the Dansbandkampen with the Casanovas in 2009. In 2018, he won the Guldklaven in the category, Singer of the Year.