The National Institutes of Health intends to award a sole source purchase order to Prolific Academic Ltd for access to an online participant recruitment platform. The platform will support behavioral nutrition studies with English-speaking adults, including parents and U.S. residents, while maintaining scientific integrity through a separate participant pool. Required capabilities include pre-recruitment eligibility estimates, longitudinal re-contact, researcher-controlled compensation, rapid recruitment, and data quality controls. Market research indicates that only Prolific can provide access to this specific participant pool and platform infrastructure. Interested parties may submit a capability statement, but no competitive solicitation will be issued.