CSI Leasing Founded in St. Louis, Missouri, in 1972, CSI is one of the most significant private leasing companies in the United States. CSI has more than 30 sales offices distributed through the US, Canada, Mexico, Brazil, Costa Rica, Germany and the United Kingdom. For more than 30 years, CSI has maintained an excellent reputation due to its seriousness, excellent service record, and rapid response time to customer requests. At CSI, we understand the importance of developing business sources and of adding real value to those relationships using creativity, consistency and our experience in operating leasing.