USG and foundations bring different strengths and confront different challenges in their philanthropic efforts. Of particular importance for sustainability are the two sectors respective time horizons and attitudes toward their own roles in seeing initiatives through to full fruition. Foundations tend to accept risk, which leads them to innovative approaches but not necessarily to long-term commitment. Indeed, many private philanthropic funderssuch as RWJFlimit the length of time or the number of times a grantee may receive support. In contrast, the federal government is more likely to fund proven strategies, which suggests the potential for USG to cultivate the growth of initiatives for which foundations planted the seed.
However, the sectors respective approaches to long-term commitment may be changing. Well-funded foundations, such as Gates, may be trending toward longer-term efforts than past foundation giving. Moreover, with federal budgets under extraordinary pressures, foundations may be in a better position than government to make such commitments (cf. San Francisco Chronicle, January 6, 2009). In any case, it is clear that the long-term solution of some problems will require long-term donor commitments, and more purposeful interaction from various donors might support such efforts. Both foundations and government appear to have embraced the philosophy of local ownership of their initiatives, which can also support sustainability.
 Some initiatives are not intended to be sustained past the original donors involvementfor example, in cases where a program is meant as a demonstration or where the problem is a passing crisis. Such cases are not within the focus of this section.