Ground improvement techniques are commonly required for construction on soft clays. In general, the most traditional construction techniques use a combination of prefabricated vertical drains, temporary surcharge, reinforcement, stabilising berms or staged construction. In order to achieve shorter construction times, alternative techniques may be adopted. Examples of these include: lightweight fills, vacuum preloading, temporary surcharge, geosynthetic-reinforced pile-supported embankments, stone columns, geosynthetic-encased columns and cement injection techniques such as deep mixing. This keynote lecture will present the results of two recent case studies in which vibro stone columns and encased columns were used to strengthen a soft clayey foundation supporting embankment loading.