The U.S. Chamber of Commerce is the world’s largest business organization representing the interests of more than 3 million businesses of all sizes, sectors, and regions. It is not an agency of the government; rather a lobbying group who represents America's businesses. In fact, it is one of the largest and most powerful groups of its kind. Their members range from mom-and-pop shops and local chambers to leading industry associations and large corporations. They all share one thing in common—they count on the Chamber to be their voice in Washington, D.C.