He retired from Congress in 2011 and his younger brother, Mario Díaz-Balart, who had previously represented Florida's 25th congressional district, succeeded him.

After leaving Congress, he started a law practice and a consulting firm, both based in Miami, Florida.

[citation needed] He was educated at the American School of Madrid in Spain; New College of Florida; and Case Western Reserve University, from which he earned a Juris Doctor degree.

[citation needed] In 1982, he ran for a Florida House of Representatives seat for District 113 as a Democrat and lost to the Republican, Humberto Cortina.

He was a sponsor of the DREAM Act which seeks to facilitate access for illegal immigrant students to post-secondary education by allowing states to have power to determine requirements for in-state tuition.

[13] He achieved passage into law of historic pieces of legislation – such as the Nicaraguan Adjustment and Central American Relief Act (NACARA), and the codification of the U.S. embargo on Cuba (requiring that all political prisoners be freed and multi-party elections scheduled in Cuba before U.S. sanctions can be lifted).

Diaz-Balart took the rule to the floor of the House for passage of the legislation that created the Department of Homeland Security and the extension (for 25 years) of the Voting Rights Act.

[citation needed] Diaz-Balart played a prominent role in the Cuban-American lobby, and was active in the attempt by relatives of Elian Gonzalez to gain custody of the six-year-old from his Cuban father.

[citation needed] In March 2010, Diaz-Balart publicly called the passage of the Patient Protection and Affordable Care Act "a decisive step in the weakening of the United States.

"[15][16] On September 29, 2008, Diaz-Balart voted against the Emergency Economic Stabilization Act of 2008[17] "American taxpayers should not have to foot the bill for the irresponsible behavior of Wall Street executives.

"[18] In 1992, Diaz-Balart defeated fellow State Senator Javier Souto in the Republican primary for the newly created 21st District.