Hyperpolarised 129Xe MRI offers a wealth of complementary information about the function and microstructure of the lungs, and in the dissolved phase, has potential for imaging perfusion and gas exchange in organs such as brain and kidneys. This talk will cover:Overview of polariser technology, RF , scanner platform and integration.Pulse sequence considerations for gas and dissolved phase xenon including the physical constraints posed by the hyperpolarised signal, T1/T2 , diffusion.Modelling of gas exchange and diffusion signal dynamics.Brief overview of clinical applications of 129Xe in lungs and other organs.