HIEs, like any other business, must have a means to be sustainable.  Sustainability simply means that an HIE brings in enough revenue to cover all of its costs.  It is incredibly important that HIEs develop a sustainability plan, understand the costs they need to account for, and implement revenue streams that can cover the costs.  This becomes even more important as grant funding dissipates.  Successful HIEs tend to take an entrepreneurial approach to their sustainability plan and think like a for-profit business.  They are continually anticipating the market and innovating their business model.  When HIEs fail to take a forward looking approach to sustainability, they risk financial stagnation.