In 2013, he defended his Ph.D. thesis in psychology, and in 2019, his doctoral thesis.
From December 2011 to March 2014, he was the head of the Department of Professional Training and Education of the Ministry of Internal Affairs of Ukraine.[1]
In 2015, he headed the Human Resources Department of the National Police of Ukraine, in 2017 he was appointed Deputy Head of this Department, and in 2019 — Head of the National Police.[3]
On January 18, 2023, he was appointed Deputy Minister of Internal Affairs of Ukraine and Acting Minister. The appointment took place after the death of Denys Monastyrsky in a helicopter crash.[1] On 7 February 2023 parliament appointed Klymenko Minister of Internal Affairs of Ukraine.[4] 321 deputies (of the total 411) voted for the relevant resolution. Klymenko received no support from European Solidarity and only 1 vote from Holos.[4]