A perspective of adhesion is offered using average property indices such as dielectric constant, dipole moment, and thermal conductivity. These indices have been derived by comparisons of dielectric theories of adhesion and cohesion with comparisons to experimental data found in the literature. For example, it was found that adhesion generally increases with increased dielectric constant, or with the inverse of the thermal conductivity, for metal substrates. It was also found that ranges in the experimental data found were primarily caused by changes in surface roughness, which meant that interaction densities were not predictable.