In this issue of PET Clinics, guest editors Drs. Abass Alavi, Andrew B. Newberg, Poul Flemming Høilund-Carlsen, and Eric Guedj bring their considerable expertise to the topic of PET-CT-MRI in Central Nervous System Disorders with Emphasis on Dementias. Top experts in the field provide an overview of PET imaging in the most common dementias and brain diseases, such as Alzheimer’s and epilepsy. Specific articles also investigate normal brain aging, long COVID, brain trauma, and human experience and consciousness.