After working as a military instructor at the Army Staff College in 1977, he was appointed to the  Supreme  Headquarters  Allied  Powers  Europe  (SHAPE)  in  Belgium and served as a project officer in the Policy Branch for three years. He then served  as  a  project  officer and Section  Chief  for  seven  years  at  the  Turkish General Staff Plans and Policy Division.

He commanded an artillery regiment from 1987 to 1989. Later, he served as Assistant Chief of Staff,  Operations  in  the Turkish  Third  Army  Headquarters  from  1989  to  1990.  He  was promoted  to  Brigadier  General  in  August  1990  and appointed to the Turkish General Staff headquarters as the Chief of Strategy and Force Planning Division.

General  Yöney served as Deputy  Assistant  Director  Plans  and  Policy  Division  in  NATO International  Military  Staff  in  Brussels  from  June  1991  to  August  1993. He subsequently commanded 19th  Infantry  Brigade and was promoted to Major General in August 1994. As a Major General, he served in  Turkish  General  Staff  as  the Chief  of  Plans and Operations Division one year, and the Chief of Strategy and  Force  Planning Division again for two years. In August 1997, he took command of the 1st Mechanized Infantry Division in Ankara. General Yöney was the Commander of the National Security College between August 1998 and August 1999 in Ankara.

He was promoted to Lieutenant General on 30 August 1999 and commanded the 6th TU Corps until August 2000. Subsequently, he was assigned as the Turkish Permanent Military Representative to NATO. 

General Yöney was assigned as Commander, Joint Command Southeast on 18 August 2003 and promoted to the rank of General on 30 August 2003.

General Yöney is married to Mrs. Emel Yöney and has two daughters.