Metastasis is responsible for the majority of breast cancer-related deaths. The metastatic spread of cancer cells is a complicated process that requires considerable flexibility in the adhesive properties of both tumor cells and other interacting cells. Cell adhesion molecules (CAMs) are membrane receptors that mediate cell-cell and cell-matrix interactions, and are essential for transducing intracellular signals responsible for adhesion, migration, invasion, angiogensis, and organ-specific metastasis. This review will discuss the recent advances in our understanding on the biological functions, signaling mechanisms, and therapeutic potentials of important CAMs involved in breast cancer metastasis.