Indentation and adhesion are considered in the context of the two experimental methods predominantly used to measure contact behavior at small length scales, instrumented indentation testing and atomic force microscopy. The typical loads and displacements applied and sensed by each measurement technique, both within the (probe + surface) contact system and exterior to it, are considered in turn. The loads and displacements are placed in the context of the atomic-scale parameters quantifying material indentation and adhesion behaviors, atomic bond stiffness and rupture force, respectively. The central role played by the probe stiffness in determining whether a contact is likely to be more indentation- or adhesion-like—or something in between—is highlighted, with an emphasis on quasi-static contact. Dynamic behavior is also considered, along with the likelihood of measurable adhesion effects appearing in typical indentation measurements of biological materials using atomic force microscopes.