Andrew Koleros

Andrew (Drew) Koleros is a systems change evaluator with over 20 years of experience designing and delivering mixed‑methods evaluations and monitoring, evaluation, and learning systems for initiatives of varying scale. He specializes in theory‑based approaches that integrate systems thinking and complex concepts into programme and evaluation design. His recent work focuses on supporting public sector and philanthropic efforts aimed at driving systems change in areas such as safe and affordable housing, climate adaptation and mitigation, and equitable health and education outcomes.

Koleros is recognized for designing and applying systems‑oriented evaluation methods that make complex change processes visible and actionable for diverse system actors. He has advanced the use of system mapping tools—integrating actor‑based theories of change, causal loop diagrams, and political economy analysis—to help funders and partners understand system dynamics, identify leverage points, and evaluate the impacts of systems change initiatives. He has also adapted a wide range of rigorous non‑experimental causal pathways methods to strengthen evidence of contribution relative to contextual factors. To ensure that evidence informs strategy, he integrates participatory sensemaking processes and innovative reporting formats, such as interactive ecosystem maps and tailored analytical briefs, that make complexity accessible to diverse stakeholders.

An experienced facilitator and trainer, Koleros has worked internationally across diverse stakeholder groups. He teaches micro‑credential courses on Theories of Change and Theory‑Based Evaluation for the United Nations System Staff College (UNSSC); co‑developed courses for the UK Evaluation Society; and lectures at Boston College on theory of change. He holds a Master's in Public Health from Tulane University. Before joining Mathematica, he served as Director of Research, Monitoring and Evaluation for Palladium’s Europe, Middle East, and Africa Regional Office. His work has been published in leading evaluation journals, and he is active in multiple professional evaluation associations and communities of practice.