After the war, Kolak held various posts: he was Secretary of the People's Assembly of Socialist Republic of Bosnia and Herzegovina, President of People's Assembly in Banja Luka, President of the Supervisory Committee, and Minister in the Government of the Socialist Republic of Bosnia and Herzegovina.[citation needed]
From 1963-65 he was Vice President of the Executive Council of SR Bosnia and Herzegovina and became President of the Executive Council of SR Bosnia and Herzegovina in 1965 and held that post until 1967.[citation needed]