The concept of hydrophobicity is commonly invoked to describe the nature of watersurface interactions and explain wettability. Intuitively, hydrophobicity describes the propensity of a surface to "repel" water, although a precise molecularly informed definition as well as its relationship to macroscopic behavior remains lacking. Nevertheless, it is widely appreciated that the extent of hydrophobicity can roughly dictate performance in a range of applications. For example, anti-fouling biomaterials require less hydrophobic surfaces, biomimetic self-cleaning surfaces require more hydrophobic surface, and water-harvesting may use materials that have specific hydrophilic-hydrophobic patterned surfaces. In these and other applications, polymeric materials are an attractive platform for potentially tailoring surface hydrophobicity, owing to a large chemical space, amenability to a variety of surface treatments, and biointerfacing or biomimetic potential. Methods to predict, characterize, and understand the hydrophobic behavior of polymers would thus have broad utility.