This book presents 204 peer reviewed articles from the 5th International Conference on Geotechnics for Sustainable Infrastructure Development (GEOTEC HANOI 2023) held on 14-15 Dec 2023 in Hanoi, Vietnam. The papers come from nearly 40 countries of the five different continents and are grouped into six conference themes: 1) Deep Foundations; 2) Tunnelling and Underground Spaces; 3) Ground Improvement; 4) Landslide and Erosion; 5) Geotechnical Modelling and Monitoring; and 6) Offshore Wind Power.