This book constitutes the proceedings of the Joint 2018 National Conferences of the Australian Society for Operations Research (ASOR) and the Defence Operations Research Symposium (DORS). Offering a fascinating insight into the state of the art in Australian operations research, this book is of great interest to academics and other professional researchers working in operations research and analytics, as well as practitioners addressing strategic planning, operations management, and other data-driven decision-making challenges in the domains of commerce, industry, defence, the environment, humanitarianism, and agriculture. The book comprises 21 papers on topics ranging from methodological advances to case studies, and addresses application domains including supply chains, government services, defence, cybersecurity, healthcare, mining and material processing, agriculture, natural hazards, telecommunications and transportation. ASOR is the premier professional organization for Australian academics and practitioners working in optimization and other disciplines related to operations research. The conference was held in Melbourne, Australia, in December 2018.