Micro- and nano-scale contacts that adhere directly due to surface forces are ubiquitous in semiconductor bonding and stacking processes as well as in AFM-based nanolithography. Understanding and characterizing the mechanics of direct adhesion in these processes is essential to advancing process capability. This presentation will discuss two different studies in which the adhesion of small-scale contacts in micro- and nanosystems were examined. First, a study of the direct adhesion of single crystal silicon components will be discussed. A microbeam-based method was used to characterize adhesion hysteresis of smooth single crystal silicon contacts in varying levels of relative humidity. The results show significant hysteresis between adhesion and separation and have implications for processes such as direct wafer bonding and nanomembrane stacking via microtransfer printing. Second, a study of the role of geometry on the adhesion of single asperity nanoscale contacts, such as those formed by an AFM tip in contact with a surface, will be discussed. Specifically, the effect of deviations in the tip geometry from the ideal parabolic geometry assumed in the classical models (e.g., JKR, DMT) was examined. A combination of analytical modeling, finite element simulations, and experiments were used to quantify the effect of changes in tip geometry on the relationship between pull-off force and work of adhesion. Furthermore, the role of roughness on the effective adhesion range is examined. The implications of both of these studies on nanomanufacturing processes will be discussed.