Metastasis is a complex, multistep biological process, involving a multitude of genes and biomolecules. Despite the successful therapeutic management of breast cancer, including surgery, chemotherapy and radiation therapy, that can control primary tumor growth, metastatic disease remains the greatest clinical challenge in oncology, as these methods are still not very effective in preventing relapses or in the management of breast cancer metastases. The knowledge of its mechanisms is still fragmentary and needs to be broadened in order to improve our therapeutic approach and influence on the long-term control of breast cancer progression. Despite the constant progress in understanding of breast cancer progression, it remains a major health problem around the world. Novel therapeutic modalities are being tested and developed, but the incidence and mortality rates are still frightening. In this paper, we review selected aspects of breast cancer metastasis, including the metastatic cascade and models of dissemination, tumor angiogenesis, disaggregation and migration of cells from the primary tumor, breaking the vascular wall, adaptation to a new environment, organotropism and dormant cells. The interactions between cancer cells and normal host cells contributing significantly to the metastatic cascade are highlighted, and a wide range of signaling and stimulating biomolecules and genes involved in the process are introduced.