In recent years many projects use deep-soil-mixing columns for the improvement of soft ground. These methods permit accelerated construction of embankments and protect adjacent facilities that might otherwise be damaged by settlements induced by the new embankment load. The design of these methods used to be more art than science. In order to put more science into the art of deep soil mixing a simplified design approach for geosyntheticreinforced, load-transfer platforms in column-supported embankments has been developed that takes into account the load-deformation response of all the important system components. Stability analysis of embankments founded on deep-mixing-method columns is complicated by the fact that multiple failure mechanisms are possible. Limit equilibrium analyses only reflect composite shearing, which is not the critical failure mode in many cases of practical interest. Numerical analyses can capture a wider range of failure modes, including composite shearing, column bending, and column tilting. An additional complication is that deep-mixed ground is highly variable, and this has a nonlinear impact on reliability analyses for columnsupported embankments. Of several approximate reliability analysis methods, the Hasofer-Lind method was found to produce the best determination of reliability compared to direct integration.