Differential treatment of cells with trypsin can be used to distinguish Ca(2+)-dependent adhesion (CDS) from Ca(2+)-independent adhesion (CIDS). Cadherins appear to be a unique family of molecules whose structure and function as adhesion molecules are protected from trypsin in the presence of Ca(2+). This unit provides protocols for preparation and analysis of cells for cadherin-dependent adhesion in short-term and long-term aggregation assays. The functions of different cadherins can be assessed in mixed aggregate assays. Fluorescence antibody-based assays are used to identify specific cadherins and their associated catenins, and transformation of cells with specific constructs can be used to assay adhesion in cells with loss of cadherin activity.