CSI Support & Development is a resident-member controlled organization that utilizes a cooperative management system and engages its resident membership in decision-making at every level of its operations. CSI was incorporated in 1945 as a mission-driven non-profit and exists solely to provide the highest quality, affordable housing communities possible for seniors. CSI has 61 properties with over 6500 units in California, Maryland, Massachusetts, and Michigan.

CSI Support & Development (CSI) is proud to sponsor Zeal Credit Union, a financial institution that serves a diverse group of 60,000+ members in Michigan. The credit union was originally established as Co-op Services Credit Union in the 1950s, and later changed its name to Zeal Credit Union in 2014. By joining the CSI cooperative, individuals also gain the benefit of eligibility to join its financial cooperative, Zeal Credit Union.

Becoming a member of Zeal is easy, and it requires a one-time membership fee of $2 to CSI Support & Development Services. This fee establishes the individual as a member of the credit union and grants them access to a wide range of financial services such as low rates, dividends, and community perks. The individual also needs to deposit $5.00 into a regular share account to open their membership in the credit union. Potential members may join through the Zeal membership application located via https://www.zealcu.org/become-a-member/

CSI has a rich history in the area, having started as Cooperative Dairy Services in the 1940s and growing to eventually merge with Fordson Cooperative in 1958 to form Cooperative Services, Inc. CSI continues to support the credit union's mission to serve its members and provide them with access to financial services that meet their needs.