Best practices for developing precision medicine diagnostics can include completing a retrospective analysis.  Obtaining enough samples to have a statistically significant study typically requires going beyond an initial institution.  There are a multitude of impediments that can frustrate the ability to rapidly identify and obtain samples.  This presentation will review these impediments by segmenting institutions into three segments: major academic medical centers, biobanks, community practices and mid-tier cancer centers.  Within each of these segments, the presentation will discuss the typical impediments.  The presentation will close with some recommendations for improving the process for both requestors and providers.