Importance Oncocardiology is a medical discipline that focuses on the identification, prevention, and treatment of cardiovascular complications related to cancer therapy. This discipline has gained interest from the cardiology community in recent years because of a remarkable increase in the number of cancer survivors and the proliferation of new cancer therapies causing cardiovascular complications, such as hypertension, heart failure, vascular complications, and cardiac arrhythmia. In this review, we provide historical perspectives, highlight new discoveries, and speculate on the opportunity created by merging the research interests and clinical practices of cardiology and oncology. Observations The old paradigm of anthracycline cardiotoxic effects is replaced by new insights that anthracycline targets topoisomerase II β to cause DNA double-strand breaks and a profound change in the transcriptome leading to the generation of reactive oxygen species and the development of mitochondriopathy. Prevention of anthracycline cardiotoxic effects should be based on inhibiting or degrading topoisomerase II β. New challenges were posed by the introduction of trastuzumab and tyrosine kinase inhibitors that revolutionized cancer therapy. The on-target cardiotoxic effects of trastuzumab were owing to a prosurvival benefit of Her2 that binds to neuregulin, whereas the off-target effect of multitargeted tyrosine kinase inhibitors may be mediated by disruption of the vascular endothelial growth factor signaling pathway or the stress-induced angiogenesis. Sensitive imaging techniques, such as global strain, and biomarkers have allowed for early detection of cardiotoxic effects. Early treatment with heart failure medications may be beneficial in preventing the development of late cardiotoxic effects. Conclusions and Relevance Close collaboration between cardiologists and oncologists is required to meet the demand of an increasing number of cancer survivors. New insights based on mechanistic studies or genetic discoveries will pave the way for better prevention, diagnosis, and treatment of cancer therapy-induced cardiovascular complications.