W. Clement Stone's father died when he was 3, leaving the family impoverished because of his gambling losses. At the age of 6, Stone began hawking newspapers on Chicago's South Side, while his mother worked as a dressmaker. At 13, he owned his own newsstand.

At the age of 16, Stone went to Detroit to help his mother in the insurance agency she had opened there. He went from office to office, making cold call (he called them gold calls) to sell casualty insurance, and he was soon making $100 a week.

One of his favorite expressions when describing his cold calling and sales abilities was that he "...Mowed them down". He devoured the Horatio Alger stories, where poor boys overcome adversity to make good.

Stone dropped out of high school to concentrate on selling insurance. He eventually received a diploma from the Young Men's Christian Association Central High School in Chicago. The remainder of his formal education consisted of a few courses at Detroit College of Law and Northwestern University.

Much of what is known about W. Clement Stone comes from his autobiography The Success System That Never Fails. In that book, he tells of his early business life which started with the selling of newspapers in restaurants. At the time, this was a very novel thing to do, which deviated dramatically from the normal practice of young boys hawking newspapers on street corners.

At first, the managers of restaurants tried to discourage him from this practice, but he gradually won them over, due in part to his politeness, charm, persistence and the fact that by and large, the patrons of the restaurants had no objection to this new way of selling his newspapers.

From there he graduated to selling insurance policies very successfully in the offices of downtown businesses. His mother was the initiator of his new career, and together they did quite well, she as the manager of the business, and he as the salesperson.

Stone ran $100 into millions with a strong desire to succeed and by putting into practice the principles in the book Think and Grow Rich by Napoleon Hill.He was the living example of the proverbial rags-to-riches protagonist in Horatio Alger's stories he loved so much. Eventually he became an 'angel' to others lifting some from the gutter, to incredible heights. One of his great successes was the famed Og Mandino, an alcoholic at the time whom Stone took under his wing. The relationship engendered a new life for Mandino who became the publisher of Success Magazine at the time.

In 1919, Stone built the Combined Insurance Company of America (a multi-level marketing company providing accident and health insurance coverage) and by 1930 he had over 1000 agents selling insurance for him across the United States. By 1979, Stone’s insurance company exceeded $1 billion in assets. Combined company later merged with the Patrick Ryan Group to form the Aon Corporation in 1987. The Combined Insurance Company of America was one of Aon's largest subsidiaries until sold to ACE Limited in April 2008 for $2.56 billion.

Stone contributed up to $10 million to President Richard Nixon's election campaigns in 1968 and 1972; these were cited in Congressional debates after Watergate to institute campaign spending limits.

One of his achievements was the creation of the W. Clement Stone and Jessie V. Stone Foundationin 2009 the Foundation gave [1]$3,805,625 to worthwhile causes.

An noted above, Stone was a proponent of the motivational book Think and Grow Rich by Napoleon Hill and associated with Hill to teach the Philosophy of Personal Achievement “Science of Success" course. Stone wrote: "One of the most important days in my life was the day I began to read Think and Grow Rich in 1937. Stone said that the Bible was “the world's greatest self-help book".

Stone explained the importance of PMA (Positive Mental Attitude) in his last interview not long before passing away. Stone said: "A positive mental attitude is necessary for achieving worthwhile success. We in America know what it is for us, for we have inherited the tenets of the Judeo-Christian faiths on which our Constitution, laws and customs have been based...Strive to understand and apply the Golden Rule...Believe that any goal that doesn’t violate the laws of God or the rights of your fellow men can be achieved".

Stone emphasized using a "positive mental attitude" to make money. His motto was: "Whatever the mind can conceive and believe, the mind can achieve with PMA." In 1960, Stone teamed up with Napoleon Hill to author Success Through a Positive Mental Attitude. The two also founded a monthly digest magazine, entitled Success Unlimited. In 1962, Stone wrote the Success System That Never Fails, in which he suggested how to become successful and have a healthy, productive lifestyle. In 1964, he and Norma Lee Browning collaborated on writing The Other Side of the Mind.

Stone gave over $275 million to charity including civic groups, mental health and Christian organizations. Stone was once quoted as saying, "All I want to do is change the world".

Among his philanthropic activities was his long-time support of the Boys Clubs of America for over fifty years (now Boys and Girls Clubs of America). Stone donated one million dollars to Rev. Dr. Robert H. Schuller to begin construction on the Crystal Cathedral. The W. Clement and Jessie V. Stone Foundation was established by Stone and his wife to support humanitarian, mental health, religious and community causes (Stone was married to Jessie for 78 years). Stone was a supporter of The Napoleon Hill Foudation which he directed for forty years. His estate contributes funding for The Napoleon Hill Foundation. Stone celebrated his 100th birthday with a gift of $100,000 to the University of Illinois at Chicago.

Stone provided much of the initial funding for the self-help organization, GROW. Stone was inducted into the Horatio Alger Association of Distinguished Americans, and was a 33rd degree FreeMason.

W. Clement Stone once stated, “Regardless of what you are or what you have been, you can still become what you may want to be.”