Alternative scaffolds offer a valuable route for generating target-binding proteins outside traditional antibody architectures. Many of these frameworks are compact, structurally robust, and well suited to loop- or surface-residue diversification. When paired with phage display, they enable efficient genotype-phenotype linkage, iterative enrichment, and flexible screening design against purified proteins, protein domains, conformational epitopes, enzyme active regions, receptor ectodomains, or selected cell-surface targets.