The Office for the Suppression of Corruption and Organised Crime (Croatian: Ured za suzbijanje korupcije i organiziranog kriminaliteta), better known as USKOK, is a body of the Croatian criminal justice system, attached to the State's Attorney Office and specializing in investigations related to corruption and organized crime.

[1] The bureau's name is a bacronym from uskok, a term used for a type of Croatian militia men, who fought with guerilla tactics against the Ottoman Empire in the early 16th and 17th centuries.

[2] Described as "one of the world's most formidable anti-corruption outfits", the agency has prosecuted 2,000 individuals and achieved a 95% conviction rate (2012), including former Prime Minister Ivo Sanader.

[3] In its 2014 EU Anti-Corruption report, the European Commission commended USKOK's ability to "carry out impartial investigations into allegations of corruption irrespective of the political affiliation or connections of those involved".

[4] But in a subsequent report in 2017, the EC noted enduring problems concerning inter-institutional coordination, and called the overall effectiveness of the institutional framework into question.