Over the last few decades, several advancements have been made in caries prevention. Sealants protect the occlusal surfaces, inhibiting bacterial growth and providing a smooth surface that increases the probability that the surface will stay clean. The purpose of a sealant is to provide physical barrier to seal off the pit or fissure, and to prevent the bacteria and their nutrients from collecting within the pits or fissures to create the acid environment necessary for the initiation of dental caries. The development of sealant materials, rationale for using sealants, recommended procedures, indications for use and factors affecting sealant retention have been explained in this chapter. A logical extension of preventive sealant strategy involves the use of resin restorative materials plus in discrete areas of caries attack on a fissured surface. These are called as preventive resin restorations. Highlights of the chapter are guidelines for sealant use in individual care and in community programs, and newer sealant materials, such as Wetbond pit and fissure sealant, illuminating sealant and sealant with amorphous calcium phosphate.