Overall, this study holds several implications for future work and consideration. We have demonstrated numerous viable methods and relevant analyses distinguishing the wetting behavior of polymer surfaces. Among the metrics examined for surface hydrophobicity, extraction of nanoscale contact angles is appealing since it can be obtained from equilibrium simulations at fairly low computational cost; however, contact-angle measurements can become ambiguous when performed with soft, dynamic surfaces. This aspect has often been avoided in prior literature by using artificially rigid polymer matrices-a practice that should be carefully and contextually considered. Otherwise, the free-energy based approaches (thermodynamic integration and indirect umbrella sampling) have comparable computational cost (ca. 3 -10× that of the contact-angle measurements), but thermodynamic integration is prone to statistical noise and requires small amounts of water, which may be of lesser interest for other analyses. We therefore favor using indirect umbrella sampling as a robust method for assessing surface hydrophobicity; rotational decorrelation times of interfacial water also strongly correlate and can provide a very computationally inexpensive metric for hydrophobicity. Finally, some of the methods and analyses employed here may be useful for more general study of interfacial physics and related phenomena. Areas of potential interest include different solute-water-polymer interactions (e.g., purification membranes ) and charge-transfer phenomena (e.g., collisional charging between insulators, 9,125 heterogeneous polymer electrolytes ).