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In many countries, essential infrastructure is built along congested coastal regions that are composed of highly compressible soft and weak soils up to significant depths. For instance, alluvial and marine clay deposits have very low bearing capacity and excessive settlement characteristics, posing obvious design and maintenance challenges for constructing tall structures and large commercial buildings, as well as for developing port and transport infrastructure. Stabilising these very soft deposits is essential before commencing construction of infrastructure. A system of prefabricated vertical drains (PVD) combined with vacuum pressure and surcharge preloading has become an attractive ground improvement alternative in terms of both cost and effectiveness. This technique accelerates consolidation by promoting rapid radial flow which decreases the excess pore pressure while increasing the effective stress. In recent decades, natural prefabricated vertical drains (NVPDs) made from biodegradable fibre such as jute and coir have also become increasingly popular because of their distinct advantages such as comparative discharge capacity and environmental friendliness. However, NVPDs can sometimes decay rapidly in an adverse environment, e.g. in highly acidic soil, which retards the dissipation of excess pore pressure. In this keynote paper, an analytical solution considering the influence of biodegredation of NVPDs on soil consolidation is proposed in addition to the overview of theoretical and practical developments of soft ground improvement via PVD and NPVD together with vacuum preloading.