This report addresses available and emerging alternative cements with the intent to facilitate the adoption of these new materials. Given the initiatives to address the sustainability of construction, owners, architects, and engineers are actively seeking alternatives to portland cement for concrete. An alternative cement is intended to be a replacement for portland cement in some applications. In some cases, alternative cements can also be used in combination with portland or blended hydraulic cements. In addition to a reduced environmental impact associated with their production and use, alternative cements offer improved performance over portland cement in some applications. Various alternative cement technologies are discussed, including their physical and compositional characteristics, methods of production, fresh and hardened properties, and example applications. Additionally, the applicability of existing tests methods for specifying alternative cements is discussed and new testing needs are identified.