hill+knowlton strategies is a global public relations consulting company, headquartered in new york city, united states, with over 80 offices in more than 40 countries. the company was founded in cleveland, ohio, in 1927 by john w. hill and had been led since 2011 by chairman ceo jack martin. on october 4th of 2018, the company announced the formation of a new leadership team with the appointment of lars erik grønntun and richard millar as global presidents, reporting jointly to jack martin, global chairman and ceo. it is owned by the wpp group.