Address him in business by his current title . You may introduce him socially as the former Ambassador to Whereverstein., currently serving as Deputy Commandant of /to[his superior officer or place of posting]Whom or whatever.
An ex-ambassador is often referred to as a former ambassador or a retired ambassador.
Ambassador William Smith, 00000 Chelsea Place, Seattle, Washington U.S.A. 0000000 (area code #) Dear Ambassador Smith: NOTE: Keep everything precise and to the point (easy reading) when writing ANYONE in an important position (even business.) People are busy and they want to read your letter with a point being made and if you can have a resolve to the problem (you don't always have too) but it's appreciated.
Former Marine Corps Commandant General James Jones.
Generally speaking Mrs (insert surname) will suffice unless one finds themselves in certain french speaking countries when it can be customary to address the wife of an ambassador as Mrs ambassador. Of course if one knows the wife personally you really can address her as you see fit. I find a friendly smack on the buttocks and a wink is usually suffice. -Rx
Andrew Young
James R. Sasser, a former three-term U.S. senator from Tennessee was ambassador to the People's Republic of China from 1995-1999.
If you are asking about the former ambassador to Norway, the most recent address we have is at the university where he has been teaching: Humphrey School of Public Affairs | 130 Humphrey School, 301 19th Ave. S., Minneapolis, MN 55455
Arnold Schwarzenegger
A former Deputy Under Secretary of the US Navy in 2008.
Salutation for a current Ambassador is His or Her Excellency. Also Ambassador and last name of and country. I believe that since former military and President and Senators etc.....retain their title....Like President Carter.....and military usually has Ret. after the last name I think as a salutation on an Envelope it would be His Excellany John A. Gavin, Ret.
I address letter to former state representative as US representative.
The former president resigned from office last year.