Learning from project experience is still lacking in the area of construction planning and control. A significant challenge is in deciding precisely ‘what’ engenders learning and ‘how’ knowledge can be reused. This study appraises critical learning situations (CLS) and the types of project knowledge to be reused to sustainably build capacity and improve the performance of construction projects. Given the underexplored area of study, an exploratory sequential mixed method research approach was adopted. Twelve semi-structured interviews were conducted with experts and local practitioners to gain an in-depth insight into CLS and reusable project knowledge (RPK) pertinent to construction projects. Further, questionnaire survey responses from 338 construction practitioners in Malaysia were analysed. The findings reveal that construction time and cost control make a significant positive impact when past project experiences enhance expert judgements and stimulate knowledge reuse on future projects. Thus, the effective and efficient management of project knowledge should be optimised and considered of strategic value, giving rise to improved competency and sustainability within the construction industry.