Dr. and Mrs. John Smith, or Dr. John Smith and Mrs. Ann Smith. John and Ann Smith is also appropriate, and might be the best choice in this situation.
You would address the letter to John Smith III. This is the proper way to denote that he is the third person in his family line with the name John Smith.
If you were sending a letter to John Smith, MD - you could address the letter to Dr. Smith.
If the letter/invitation is primarily to the reverend but also her husband: Rev. Mary Smith and Mr. John Smith If the letter/invitation is primarily to the husband but includes the wife: Mr. John Smith and Rev. Mary Smith If it is strictly a business letter and not church related: Mr. & Mrs. John Smith
* Proper address for a General and his wife: General & Mrs. John Smith.
The proper way to address that letter would be "Mr. and Mrs. John Doe."
Best I can do on this one: Since the person is not officially an ambassador yet, you would address the letter as follows: Dr. John Smith Ambassador Designate to Oklahoma <<at his present address>> In the greeting of the letter, refer to him by his present title: Dear Dr. Smith, etc. In the opening of the letter, it is always proper to congradulate him on his appointment. After his becomes official, then you would address the letter to: Honorable Ambassador John Smith Embassy of the United States 123 Any Street Omro, Oklahoma 12345 and in that greeting: Dear Honorable Ambassador Smith...
When addressing a letter to a married couple where the husband is a Jr., you would write: Mr. John Doe Jr. and Mrs. Jane Doe. The Jr. suffix is included after the husband's name to indicate that he is the son with the same name as his father. It is important to use both spouses' names in the salutation to ensure both individuals are properly acknowledged.
The salutation used for the envelope address can be either Dr. John Smith and Dr. Jane Smith, or Drs. John and Jane Smith. If you are writing a letter to both doctors, then he greeting in your letter can be Dear Drs. Smith.
dr Mary smith would be the correct way
Dear Mr. John and Rev. Sally Smith,
For the salutation you would write: Dear Mr. (or Mrs. or Ms.) Smith On the envelope you would address it as: The Honorable John (or Jane) Smith American Consul General Address
Dear Sirs / Messr's / John Doe and Jim Smith, ESQ.