Radiochemistry for Positron Emission Tomography “Radiochemistry for Positron Emission Tomography”, Nature Communications, 2023, 14, 3257. The concept translational radiochemistry is introduced herein to emphasize the unique characteristics of PET chemistry aimed at human translation and routine radiopharmaceutical production. To qualify any novel radiochemical method from benchtop discovery as translational radiochemistry, we evaluate it not only by its radiochemical yield and molar activity, but also by the feasibility and translatability of automation or remotely-controlled radiosynthesis in a hot cell, reproducibility and regulatory compliance in a clinical production / manufacturing environment (eg. cGMP process) with the operation, participation and approval of a diverse team, including cyclotron engineers, radiochemists, QC/QA analysts, formulation specialists, radiopharmacists and nuclear radiologists. As such, translational radiochemistry is refined as scalable, robust and reproducible PET chemistry that consistently provides high-quality radiopharmaceuticals, meeting a predefined set of specifications for human use, which is critical to protect patients from unnecessary toxicities and ensure the best possible diagnostic care.