A critical determinant of host range and specificity relies on the ability of pathogenic bacteria to recognize eukaryotic cell surface molecules via specialized adhesins. The specific adhesin-receptor interaction allows pathogens to tightly bind to their target cells, thereby facilitating the colonization of host tissues. Therefore, the identification and characterization of bacterial adhesins is a major topic in infection biology. This chapter focuses on a rapid and simple method for the analysis of adhesin-receptor interactions that permits the characterization of receptor binding properties at the level of single bacteria. Accordingly, this methodological approach is ideally suited for the analysis of adhesins expressed in a phase-variable manner and for the study of heterogeneous bacterial populations. Besides focusing on the receptor-binding assay, this chapter describes the production of fluorescence-tagged soluble host receptor domains required for conducting this assay.