In November 2020, the DOEN Foundation, in partnership with SELCO Foundation commissioned an external evaluation of SELCO Foundation's ecosystem approach, which has been pioneered by the organization over the last decade. SELCO’s energy access ecosystems are built to secure a sustainable co-evolution of energy access and its productive use, in the following steps: SELCO identifies the opportunity for interventions and engages in innovation and incubation. This spurs two virtuous cycles. First, every successful intervention enables an ecosystem to nurture and support new product or service providers who earn enough to pay for their share of energy demand, strengthening all actors supporting the intervention. Second, every new installation brings more customers to the incubated technology-providing solar enterprise, who eventually anchors mature interventions and lets the ecosystem builder exit. Both cycles can co-evolve with relative independence. The evaluation focused on two sets of research questions. The highest emphasis was on a set of systems questions: How do we define the “ecosystem approach”? How well does the approach fare as compared to its own potential and to project-based approaches for achieving the desired impact? Is the approach worth replicating elsewhere? Can it be replicated? If so, under what conditions?