We have illustrated how mucin-like glycopolymers can be assembled into glycocalyx models with defined physical (e.g., thickness, mesh size) and tunable chemical (e.g., target glycan concentration) properties, and how such glycocalyx models can reveal the impact of the glycocalyx microenvironment on multivalent protein binding (e.g., avidity and selectivity). The modular assembly strategy facilitates the design of glycocalyx models of varying complexity. More complex structures could be achieved, for example, by attaching different glycans to the same backbone, or by copresenting short and long glycopolymers for a stratified presentation of multiple glycan types, thus enabling exploration of heteromultivalent binding processes. Glycocalyx models should also be versatile for the mechanistic analysis of binding affinity and selectivity of other (endogenous or exogenous) glycan-binding proteins or biomacromolecular complexes (e.g., viruses). Another broad area that is functionally important yet poorly understood and thus worthy exploration is the mechanism of transport of toxins and other glycan-binding proteins in glycocalyces.