This study’s aim is investigating the impacts of the determinants of knowledge management on organisational sustainability. It investigates the differences in performance among ISO 9001 certified and non-certified firms. The study uses data collected from 156 employees of various private firms in the Kurdistan Region of Iraq. It uses the partial least squares method to test the hypothesised model and the independent samples t-test toelaborate on the differences between ISO 9001 certified and non-certified firms. The results show that knowledge storage plays a key role in knowledge generation, sharing, and utilisation. It is also observed that knowledge management has a significant impact on organisational sustainability. Firms in the Kurdistan Region of Iraq fail to generate management knowledge due to their weak document storage capacities. This paper discusses the theoretical and practical implications of their weak document storage capacities and makes some suggestions for improving this situation.