The Chief of the Defence Staff (CDS) is the highest ranking military officer in the Sri Lankan Armed Forces. The Chairman outranks all respective heads of each service branch Chief of the Defence Staff (CDS), responsible for coordinating joint armed force's operations. However the respective service commands have much autonomy for their deployments.

However overseas inter service corporations and the implementation of joint operations of the Sri Lankan military Coordination of inter service in joint operations is handled by the Office of the Chief of Defence Staff The CDS is the Chairman of a Committee made up of service commanders and is a member of the National Security Council. Air Chief Marshal WDRMJ Goonatilake RWP & bar VSV USP ndc psc currently functions as the Chief of Defence.

The origins of the Office of the Chief of Defence Staff could be traced back to the Joint Operations Command (JOC) established in 1985 due to the need of co-ordination of operations among the tri-services and the police with the escalation of the Sri Lankan Civil War. the Joint Operations Headquarters (JOH). The JOH was created in 1999 replacing the civilian Joint Operations Bureau which had existed briefly in 1999. The duties of the Chief of the Defence Staff CDS was extended by the Chief of Defence Staff Act No. 35 of 2009.x..

The Chief of the Defence Staff was appointed to the highest rank in the branch of the Sri Lanka armed forces to which he belonged (equivalent to a US "four-star" rank) being a General, an Admiral or an Air Chief Marshal. Accordingly to the new Bill, the President of Sri Lanka appoints to the post of Chief of Defence Staff any persons presently serving as Commander of the Army, Navy or the Air Force, to function under the direction, supervision and control of the Permanent Secretary to the Ministry of Defence.