President Calvin Coolidge has been quoted as saying that the "the business of America is business." A firm supporter of laissez-faire, Coolidge 's policies were aggresssivlely pro-business. For instance, through his appointees, he transformed the Federal Trade Commission from an agency meant to regulate corporations into one dominated by big business. Twice vetoing the McNary-Haugen bill to aid agriculture (1927 and 1928), and pocket-vetoing a bill for government operation of the Muscle Shoals hydroelectric plant, Coolidge further demonstrated his belief in laissez-faire.
In addition, the presence of such men as Herbert Hoover and Andrew Mellon added to the business tone of President Coolidge's administration. For, Coolidge supported Mellon's program of tax cuts--which, of course, helped business--and economy in government. And, through his public remarks, unfortunately, he encouraged the reckless stock market speculation that became his nemesis and that of the nation as it was unprepared for the economic collapse that followed.
President Calvin Coolidge, who succeeded to the White House after the death of Warren Harding, agreed with Herbert Hoover that government should stay out of the business of big business. Coolidge's appointments to the Federal Trade Commission and the Insterstate Commerce Commission posed few restrictions on business activities. Regulations were "thin to the point of invisibility." Coolidge also drastically reduced the Federal Income Tax by signing the Revenue Acts of 1926 and 1928. Although big business paid most of the nation's taxes, their total amounts were greatly reduced. These acts are often considered a major cause of the Great Depression.
I agree with the first answer that Coolidge transformed the FTC. But I do not think that is the most important thing he did.
Conservative historians point to Coolidge as one of the best presidents ever. The major thing he did that they like is that he pushed through Andrew Mellon's tax plan. This cut taxes on the rich. So this is something that he actually did rather than just something he said.
Coolidge also allowed Hoover (his Secretary of Commerce) to set up all sorts of commissions that helped businesses find ways to improve their products and their distribution nets and such.