Carcinoembryonic antigen (CEA)-related cell adhesion molecule 6 (CEACAM6) is a member of the CEA-related cell adhesion molecule (CEACAM) family. CEACAMs bind to themselves and other family members to carry out numerous cellular functions, including proliferation, signaling, differentiation, tumor suppression, and survival. CEACAM6 is a single-chain, glycosylphosphatidylinositol (GPI)-anchored, highly glycosylated protein that is normally expressed on epithelial cells and granulocytes. CEACAM6 mediates homophilic and heterophilic cell adhesion with other CEA-related cell adhesion molecules, such as CEACAM5 and CEACAM8. Heterophilic interaction with CEACAM8 occurs in activated neutrophils, and plays a role in neutrophil adhesion to cytokine-activated endothelial cells. High levels of CEACAM6 expression are also observed in several different cancers. In cancer, CEACAM6 promotes tumor progression, migration, invasion, and metastasis, and therefore is considered a target for therapeutic intervention.