HMS has a number of affiliations with companies both within and outside of the shopping center industry. A few of these include:
- Access One ATM, Inc. A New York City based financial services firm, specializing in the placement of revenue-sharing ATM's in malls, movie theaters, restaurants, shopping centers, office buildings, and luxury residential buildings.
- Horizon Realty Services, Inc. A Chicago-based, full service, retail real estate firm.
- Summit Strategies, LLC. A suburban Washington, DC company, specializing in helping businesses increase their cash flow through expense reduction initiatives.