Following graduation, Charles went to work as a consultant for Arthur D. Little, a large consulting firm. After only two years at Arthur D. Little, his father summoned him home to help him manage the medium sized oil company, his father then owned and managed. The father threatened his son that if he did not return home, he would sell the firm. Charles apparently got the message, and went to work for his father’s firm. From 1961 to 1963, he served as a vice president of Koch Engineering, the engineering arm of his father’s company. He was promoted to president of Koch Engineering in 1963, and served in that capacity until 1971. But before the end of his presidency of Koch Engineering, in 1966, his father appointed him to the presidency of the entire company. In the following year, in 1967, his father passed away, and Charles became the chairman and chief executive officer of the firm, which was then renamed Koch Industries, a name the firm holds until today. Over the years, Charles Koch has been an outstanding executive, especially if measured by the growth of Koch Industries. When he first took over the company in 1967, the firm was a medium sized oil firm with annual revenues of about $ 180 million, and valued at about the same amount. Today, Koch Industries has grown more than 500 fold. Charles Koch is also a generous contributor to many worthy causes. He is the founder or co-founder of a number of foundations, many of them in support of free markets and usually with a conservative economic approach.