ABSTRACT Support is requested for a Keystone Symposia conference entitled Circulating Metabolic Intermediates as Fuels and Signals, organized by Drs. Sven Enerbäck, Joshua Rabinowitz and Sarah-Maria Fendt. The conference will be held in Snowbird, Utah from October 8-11, 2023. Metabolic diseases such as stroke, heart disease, diabetes, cancer, obesity, and NASH remain major causes of death and disability. One reason for this is due to the incomplete understanding of metabolism and its regulation. New data indicate that metabolites normally viewed as wastes or benign intermediates are actually very important fuels and signals. For example, lactate has emerged as an important energy substrate and succinate as a driver of muscle remodeling, reflecting the many underexplored roles of circulating metabolic intermediates. The importance of such intermediates, as opposed to classical “fuels” like glucose, amino acids and fat, opens a new perspective on how metabolism is controlled. Thus, this field is primed for further breakthroughs, both in understanding of new biology and in offering new targets for intervention. This Keystone Symposia conference will bring together the leading experts in the field to review the latest research and discuss challenges the field is facing. Finally, this conference is being held jointly with the Keystone Symposia conference on Mechanisms of Microbiota-Immune Interactions-Towards the Next Decade. It is anticipated that this paring will lead to new scientific collaborations and the implementation of new technological approaches directed at understanding the underlying mechanisms of microbiota-immune and -metabolic interactions.