Can an NGO really sustain itself?

What does sustainability mean to an organization? Is it the freedom to exist through long-term foundation grants? Is it the independence to operate through multi-year government funding? Is it the ability to attract and retain major donors? Or is it the capacity to generate revenue through programs and services?

The reality is NGOs need support, often from more than one source. Why? Because few (if any) funding sources provide the type of guaranteed support organizations need to support operations and programs in a consistent manner. This is especially true in an environment where more organizations find themselves competing among the same sources of funds.