For-profit education in the United States (known as for-profit college or proprietary education in some instances) refers to higher education educational institutions operated by private, profit-seeking businesses. Historically, most colleges and universities in the US have been non-profit, but for-profit institutions rapidly grew in number and size in the late twentieth century. Although supporters of for-profit higher education have argued that the profit motive encourages efficiency, the for-profit educational industry has received severe negative criticism because of its sales techniques, high costs, and poor student outcomes. In some cases operators of for-profit colleges have faced criminal charges or other legal sanctions.