Metastasis is the dissemination of neoplastic cells from the primary tumor, and their colonization and growth in another part of the body. The process of metastasis is orchestrated by a complex network of biological events, and our understanding of the processes that regulate metastasis has significantly improved. This open access book provides an in-depth analysis of our understanding of the molecular mechanisms, detection, and clinical management of metastatic cancer. Updates are given on molecular imaging of brain metastasis and recurrence, management of pulmonary nodules for the early diagnosis of lung cancer, surgical management of both primary and metastatic lung cancers, genomic landscapes and tumor evolution of metastatic gynecological cancers, epigenetic changes in metastatic ovarian cancer, microRNAs in metastasis of prostate cancer, hematological toxicity of radiation therapy for bone metastasis, DNA damage response in cancer metastasis, tumor endothelial cells and angiogenesis in cancer metastasis, apoptosis-induced compensatory proliferation in cancer, the potential of targeting apoptosis to overcome chemotherapy resistance, and features of metastatic Ewing sarcoma. This open access book is aimed primarily at clinicians and scientists, but many areas will also be of interest to the layperson.