Metastasis of cancer via the bloodstream is a major factor in the diagnosis, treatment, and prognosis of patients with cancer. Key events in hematogenous metastasis occur in the microvasculature. This is a brief, selective review of some interactions involving cancer cells and the microvasculature in pathological sequence, specifically:1) intravasation of cancer cells;2) the arrest of circulating cancer in the microvasculature;3) cancer cell trauma associated with arrest;4) microvascular trauma; 5) the inflammatory and6) coagulative responses associated with arrest; and7) the fate of arrested cancer cells. The evidence shows that in addition to providing routes for cancer cell dissemination and arrest sites for cancer cell emboli, the microvasculature, through a series of complex interactions with cancer cells, controls the efficiency of and acts as a rate regulator for the metastatic process.—Weiss, L.; Orr, F. W.; Honn, K. V. Interactions of cancer cells with the microvasculature during metastasis.FASEB J.2: 12‐21; 1988.