Several main healing agents currently used in self-healing nanotextured materials are discussed in this section. These include dicyclopentadiene (DCPD) and Grubbs’ catalyst (Sect. 2.1) and dimethyl siloxane (DMS, a resin monomer) and dimethyl-methyl hydrogen-siloxane (curing agent) polymerized as poly(dimethyl siloxane) (PDMS, Sect. 2.2). Several other elastomers used for self-healing are discussed in Sect. 2.3. Self-healing agents can also comprise epoxy-hardener systems (Sect. 2.4), and gels (Sect. 2.5).