This paper introduces the conceptualization and application of a method to analyse the decision making process of New Zealand’s State Highway Organisations (SHO) during extreme events. The aim is to obtain an unbiased and complete overview of the strengths and weaknesses of the current decision making. Procedures and metrics to analyse the Quality of Decision Making (QDM) are proposed, based upon the study of theoretical and practical concepts of decision making processes. QDM analysis was applied to 3 real events and 4 exercises, which have been observed since 2005. The results of the QDM analysis indicate that SHO are capable, experienced and competent in dealing with major disruption or crises that may affect the State Highway Network of New Zealand. SHO have achieved High and Regular levels of resilience in terms of decision making activities during emergency response events and exercises.