Determines how well an adhesive "wets-out" or flows uniformly on the surface being bonded to. High surface energy materials, e.g. stainless steel and glass, offer excellent bonding characteristics. Low surface energy materials, e.g. molded polypropylene, resists "wetting-out" and require the use of more aggressive adhesive or a special surface treatment for proper bonding.

Surface energy quantifies the disruption of chemical bonds that occurs when a surface is created. In the physics of solids, surfaces must be intrinsically less energetically favourable than the bulk of a material; otherwise there would be a driving force for surfaces to be created, and surface is all there would be (see sublimation (physics)). Cutting a solid body into pieces disrupts its bonds, and therefore consumes energy.