Interfaces between organic and inorganic materials are of critical importance to the lifetime of devices found in microelectronic chips, organic electronics, photovoltaics, and high-performance laminates. Hybrid organic/inorganic materials synthesized through sol-gel processing are best suited to address these challenges because of the intimate mixing of both components. We demonstrate that deposition from heterogeneous sol-gel solutions leads to the unique nanolength-scale control of the through-thickness film composition and therefore the independent optimization of both the bulk and interfacial film properties. Consequently, an outstanding 3-fold improvement in the adhesive/cohesive properties of these hybrid films can be obtained from otherwise identical precursors. © 2013 American Chemical Society.