The liver represents a frequent site for metastatic disease, in addition to being a site for primary cancer. Hepatic metastases from certain neoplasms, such as colon, neuroendocrine, melanoma and gastrointestinal stromal tumour have a distinct predilection to metastasize the liver, which in many cases may represent the only or the dominant site of disease. In these circumstances, cytoreduction via surgery or in situ ablative techniques aims to influence the natural history of the disease progression and improve clinical outcomes.Liver directed therapy utilising yttrium-90 microspheres represents a recently introduced in situ multidisciplinary cancer therapy that has caught the attention of many physicians faced with the challenges of treating these complex patients. Although similar to other forms of trans-arterial liver directed therapy, there are discrete differences and potentially fatal treatment consequences unique to this therapy. This objective of this review article is to provide the reader a basis for understanding the therapeutic principles, patient exclusion criteria, pre and post therapy investigations and salient clinical results in the two most commonly treated disease types; metastatic colorectal cancer and hepatocellular cancer.