Rigorous impact evaluation : cross-section analysis - main report / giz, Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH ; evaluators and authors of the report: Michael Florian (GIZ evaluation unit, senior expert corporate strategic evaluations), Franziska Krisch (GIZ evaluation unit, senior expert corporate strategic evaluations), Tatjana Till (GIZ evaluation unit, expert corporate strategic evaluations), Sophie Hermanns (GIZ evaluation unit, junior expert project evaluations) ; contributors: Wolfgang Stuppert (Camino gGmbH), Carroll Patterson (SoCha llc)