This specification pertains to quicklime and hydrated lime, either high calcium, dolomitic, or magnesian lime, for use in stabilization of soils. Quicklime and hydrated lime act on clay soils and may render such soils suitable for highway construction and other load-bearing applications. In most cases, lime causes finely divided clay particles to agglomerate into coarser particles, which improves load-bearing properties, and subsequently the lime-treated soil hardens by chemical reaction. No attempt is made to present requirements for by-product lime, commercial lime slurry, etc. Specification requirements for these materials could be better determined on a local basis.