Delve into the intricacies of QCD Dispersion Relations in this third lecture delivered by B Ananthanarayan as part of the School for Advanced Topics in Particle Physics (SATPP) at the International Centre for Theoretical Sciences. Explore advanced concepts in Effective Field Theories (EFTs) over the course of 77 minutes, designed for postdoctoral fellows and advanced PhD students in theoretical particle physics. Gain insights into systematic approaches for describing physics at various scales using relevant degrees of freedom, essential for understanding phenomena from TeV scales to meson and baryon observables. Benefit from a comprehensive program that aims to provide both theoretical foundations and practical tools for critical analysis in particle physics research.