Does your organization use market-based approaches to help solve the global safe drinking water and sanitation challenge? Are you based in the U.S. (501c3) but operating internationally? If so, please review the Laird Norton Family Foundation's recently-issued open call for Letters of Interest.
From their website:
The objective of this open call is to identify strong organizations working in innovative ways to address water and sanitation challenges in the developing world. We will consider funding programs that 1) use market-based approaches to address water and sanitation challenges, particularly those developing replicable or transferable solutions; or, 2) engage in efforts that advance your organization's field of work or build your organization's internal capacity to offer water and sanitation solutions in new or innovative ways.
Let me know how it goes...