Holiday Systems International (HSI) is an exclusive Members-Only service. The holiday “systems” have been designed as exclusive membership benefits and will maximize your vacation value! Private enrollment with HSI provides its members with a valuable “Wholesale-Direct” status not available to the general public. This relationship allows its members to save thousands by going directly through HSI for a variety of vacation services. You can count on HSI’s outstanding record and its uncompromising commitment to its members.