Neuroendocrine neoplasia (NEN) represents a diverse group of tumours arising in almost every tissue of the body. Variation in the tissue of origin, grade and mutational signature of these tumours has profound impact on their presentation and prognosis. However, because each subtype is individually rare, standard clinical trial designs are difficult and rarely performed leading a lack of evidence on which to base management decisions. This provides a strong argument for a precision-medicine approach based on in-depth characterization of tumour biology in individual patients. Advances in genomic technologies have demonstrated that NEN commonly has a hereditary basis and that sporadic cases also involve common pathways. While the cost of sequencing tumours has decreased markedly in recent years, the heterogeneity that is common in NEN poses a challenge for use of this technology in isolation. Molecular imaging provides a platform for in vivo characterization of tumour biology on a whole-body scale with the ability to also monitor the evolution of tractable therapeutic targets. Our research focuses on drawing a link between imaging phenotype and genotype in various NEN, particularly including phaeochromocytoma/paraganglioma (PPGL), Merkel cell carcinoma (MCC) of the skin and pancreatic NEN (panNEN). Understanding the drivers of these diseases in individual patients will aid in prognostic stratification, molecular imaging staging and surveillance paradigms and, hopefully, in selecting optimum choice or sequencing of treatment. In PPGL and panNEN, understanding of the process of dedifferentiation is important, while for MCC, better understanding of the role of the immune system and the differences between disease arising from sun-exposure and that related to polyoma viral infection are key research objectives. How genomics will complement “theranostics” will be discussed.