In my work in Haiti, I have equated sustainability with: living on after an initial investment was complete. We have tried to do this by designing initiatives in cooperation with local participants (reciprocity, resipwosite in Creole) and in a way that can be supported through local means and that make sense in the context. An example of this was the Digital Mentoring Project. We used tools that were already familiar (cellphones) but with a novel approach (connecting principals - across Haiti - in a professional learning community through their phones). The initiative was completed in 2014 but principals continue to use the framework to problem-solve and to share resources.
When I have talked about the concept of sustainability with partners in Canada, the US, and in Haiti, I have tended to use the words capacity-building instead of sustainability. What we are doing in Haiti is investing in social capital, the ability of people to achieve well-being through social interactions. We have done this specifically through supporting an improved educational environment. Thus, the work we have been doing in investing in teachers and principals, through workshops on school leadership, supporting special education services for children, building opportunities for girls in engineering, and supporting teachers' knowledge of science and mathematics, is building the social capital of educators in northern Haiti.
Is it sustainable? Yes, because it is building individual and collective capacity.
I often use a Haitian expression to describe the capacity-building work we are invested in - it probably provides a better description of sustainability than I can in just a few words: