Targeting strategies for drug delivery applications rely on targeting moieties (i.e., peptide, antibody) specific to the desired cell surface receptor or protein of interest. However, current targeting strategies are limited to previously identified epitopes/ligand pairs. The field of phage display opens up the targeting moiety options whereby new epitope/ligand pairs may be discovered through well-designed biopanning assays for the target cell population of interest. Here, we provide a detailed protocol to perform phage biopanning assays on adherent cell cultures. The methods described here may be modified to user-specific targeting interests.