This Funding Opportunity Announcement (FOA) announces an administrative supplement program to provide funds to NCI- and NIDDK-supported research projects for validation studies of new analytical chemistry methods. These methods must have been developed or be under development by the awardees during the active parent grant. They must be methods used to identify and quantify constituents (bioactive and other chemical marker constituents and/or their metabolites, adulterants, or contaminants) in products intended for oral administration in humans or in biological specimens such as urine, plasma, or animal tissues. As test agents the products studied may be investigated in vitro or in vivo. The products under investigation in parent grants may be dietary supplements (including vitamins or other bioactive compounds), foods, and other orally administered natural products or their raw source materials.