PET/CT imaging of insulinoma is a case study in precision diagnostics. This talk will describe the clinical utility of PET imaging for insulinoma localisation in both sporadic and syndromic disease (e.g. MEN1) and how molecular imaging phenotype reflects the underlying disease biology. I will also discuss how PET imaging phenotype can be used to stratify patients as being suitable for Peptide Receptor Radionuclide Therapy for both hormone and oncologic control in patients with advanced disease.