Previously,FPSC used to select the A.D's in MoD.However ,for the last 5 or 6 years,ISI itself sellects its civilian personnel.Basically,it is the prime"External " intelligence agency of Pakistan.But due to dominance of armed services personnel ,it looks as an agency of military only( a purely military agency is MI) .It is said that in the era of Ayub Khan ,responsibility of security of Pakistan was entrusted to it.As per my knowledge,civilians too are given field jobs and an A.D is usually promoted upto Director level.It is upto the incumbant of post that he/she cultivates good relations with his uniformed colleagus.Nevertheless,the role of civilians may be characterised as a nuanced one instead of a proactive one.