Recent innovations in polarization of noble gases and solid state biologically active compounds such as 13C-pyruvate have enable new applications of MRI for the study of functional parameters such as lung ventilation and cancer metabolism. These methods have put increase demands on acquisition speed and rf-coil sensitivity in order to address the non-equilibrium spin-lattice (T1) decay of these agents and multi-nuclear nature of the signal detection problem, e.g. imaging conventional proton and the polarized nucleus either sequentially or simultaneously. This talk will introduce the methodology behind polarization and methods to improve polarization levels and image quality using dual-tuned coil designs and fast MRI methods. Several applications of polarized MRI to study lung function and metabolism will be presented.