One area of interest in bioadhesion that has not been emphasized within the adhesion science community relates to the disaggregation of cells which occurs when cancer metastases arise. Metastasis involves the distribution of cancerous tumor cells from a large localized tumor. The resulting spatial separation of the cancerous masses makes treatment more difficult. Making use of biochemical and cellular assays, detailed mechanisms for the cell detachment processes involving cadherin cell adhesion molecules have been proposed. This paper reviews proposed mechanisms for metastasis from a cellular adhesion perspective and the testing methodologies that have been utilized. Additional understanding might be gleaned from considering the loss of cell adhesion molecules and the overall disaggregation process from a particle adhesion perspective. Several pertinent theories are presented as well as a brief discussion of areas for future effort.