The complex relations between cancer and its environment are considered as a metastatic cascade. This review is focused on fundamental steps of the metastatic process including cell-cell adhesion, intravasation and extravasation of metastatic cells, underlining the role of cell-matrix interactions and proteolytic mechanisms in migration of carcinoma cells. The regulatory functions of the tumour microenvironment and the complexity of the signalling pathways are discussed. The genetic background as an important determinant of metastatic efficiency is indicated, and mechanisms of metastatic predilection for the specific organ site are pointed out. A better understanding of the linkage between genetic and epigenetic events in multistep cancer development may result in a promising approach for new forms of cancer therapy.