Traditionally, invasive and expensive biopsies have been required to collect the amount of tumor sample needed to perform next-generation sequencing. Technology developments have enabled us to implement “low input” protocols, which allow for reliable sequencing of low quantity and quality genetic samples. In addition, we’ve developed targeted gene panels that rely on cell free DNA, which can be found circulating throughout the bloodstream. These panels direct our sequencing efforts on the specific genes or gene regions that have a known or suspected association of the cancer of interest. With these new technologies and tools in place, in some cases a simple blood draw may be all that is required to interrogate the genome of a patient’s tumor.