From Longman Business Dictionarycritical success factorˌcritical sucˈcess ˌfactor abbreviation CSFCOMMERCEMARKETING [countable usually plural] the most important things that a company does to make it successful and likely to make a profitA critical success factor was the establishment of a close relationship with a local firm of surveyors.What is important is how IT serves the critical success factors of business across all sectors. → factor