President Obama smiles after signing into law the State Children's Health Insurance Program (SCHIP) in the East Room of the White House in Washington, Feb. 4, 2009. Rep. Henry Waxman (D-Calif.) stands directly behind the president.

Rep. Henry A. Waxman (D-Calif.) announced Thursday that he will retire after serving 19 terms in the House of Representatives. Known as a prolific legislator, he played a major role in the passage of numerous laws over his four decades in Congress. Here are some of the laws he has helped pass. (Source: House Energy and Commerce Committee Minority Staff).