Nathan D. Clark graduated from Spring Hill College of the society of Jesus in Mobile, AL in 1977. He received the Juris Doctorate degree from University of Mississippi in 1980, where he served on the Mississippi Law Journal.

In 1981, Clark received the Masters of Laws in Taxation degree from University of Miami in Coral Gables, FL, where his studies focused on business entity taxation.

After graduation from University of Miami, Clark joined the Miami office of the nationally known tax firm, Culverhouse, Tomlinson, Mills, Anderson and Cone. The firm was headed by Hugh F. Culverhouse, a tax lawyer with a national reputation and the founder-owner of the Tampa Bay Buccaneer NFL football team.

Nathan D. Clark is a member of the Mississippi State Bar and the Florida Bar, as well as all the courts of those states. In criminal law, he regularly practices before the federal U.S. Courts of Appeals in the Fifth and Eleventh Circuits, and in all divisions of the federal U.S. District Courts for the Southern Districts of Florida and Mississippi.

Nathan D. Clark has been admitted to practice before the United States Supreme Court. He has served on the Federal Court Practice Committee of both the Dade County Bar Association and the Florida Bar.