For CIA: Tom Clancy.

For pre CIA (OSS circa WW II): W.E.B. Griffin, the Honor series and Men at War series

Aviation: Dale Brown

Medical: Robin Cook, and to an extent, Michael Crichton

Hope this helps

I have seen some of his movies.. I especially like Red October.

unless you count the stuff he "wrote with other authors," or the nonfiction material.

The Jack Ryan books are the heart of what he did. In publishing order:

The Hunt for Red October
Red Storm Rising
Patriot Games
The Cardinal of the Kremlin
Clear and Present Danger
The Sum of All Fears
Without Remorse
Debt of Honor
Executive Orders
Rainbow Six
The Bear and the Dragon

Thriller writer. He actually was in the CIA, so he knows what he's writing about.

I'll look him up!

John le Carré's George Smiley novels. British spy's...

Barry Eisler's not a CIA thriller, but I am enjoying the books.

I guess John le Carre's might work. I'll look him up after i finish the Rain series.

Also Stella Rimington (former head of MI5) is now a novelist.

The Grey Man series by Mark Greaney

Mark Greaney is the bestselling author of the Gray Man, On Target, and Ballistic. He is also coauthor of Locked On and Threat Vector, by Tom Clancy with Mark Greaney. Mark lives in Memphis, Tennessee

Learn more at MARKGREANEYBOOKS.COM

I liked this series.

Also, Brad Thor...I know, he is an ultracon though his Harvath series is good. IMO though Flynn (Rapp) was the best I've read so far.

John LeCarre

Those are a good start. Vince Flynn is great.

Lee Child, Robert Ludlum (Jason Bourne), John le Carré, James Morcan and one of my favorite new authors, Conrad Brasso (Hunting the Midnight Shark).

and possibly David Baldacci. His are not always CIA but he's a good storyteller like Grisham.

Have you read all of Dan Browns? Digital Fortess for example was good and not as well known.

First book in the series is The Tourist.

There is a new one on Amazon called THE PEARL SPIDER. It has 4 star reviews. The story is set during the Vietnam War. It's also on the Kindle share program.