This Funding Opportunity Announcement (FOA) will support extramural research to investigate and mitigate challenges facing clinical assay development and subsequent analytical validation due to preanalytical variability in tumor tissue biopsies, blood biospecimens utilized as liquid biopsies", or other biospecimens as described in this FOA. Extramural research funded under this FOA may include investigations of preanalytical variability associated with the procurement and study of small biopsies (core biopsies, small excision samples), blood utilized for "liquid biopsies", tissue swabs, tissue secretions, pleural and esophageal aspirates, feces, or bodily fluids like sweat, urine, CSF, breast milk and saliva. Investigator-designed experiments will explore how different biospecimen preanalytical conditions affect emerging and clinically relevant biomarkers quantified by a variety of testing platforms. The results from this research program will improve the understanding of how analytical quantification of clinically relevant biomarkers is affected by variation in biospecimen collection, processing, and storage procedures. The overall goal is to expedite biomarker clinical assay development through evidence-based standardization of biopsy handling practices.