Providing aid in times of increasing humanitarian need, limited budgets, and mounting security risks is challenging. This paper explores in what organisational circumstances evaluators judge, positively and negatively, the performance of international non-governmental organisations (INGOs) in response to disasters triggered by natural hazards. It assesses whether and how, as perceived by expert evaluators, CARE and Oxfam successfully met multiple institutional requirements concerning beneficiary needs and organisational demands. It utilises the Competing Values Framework to analyse evaluator statements about project performance and organisational control and flexibility issues, using seven CARE and four Oxfam evaluation reports from 2005-11. The reports are compared using fuzzy-set Qualitative Comparative Analysis. The resulting configurations show that positive evaluations of an INGO's internal and external flexibility relate to satisfying beneficiary needs and organisational demands, whereas negative evaluations of external flexibility pertain to not meeting beneficiary needs and negative statements about internal control concerning not fulfilling organisational demands.