Owing to ultrahigh energy density (of ~ 3600 Wh kg− 1), rechargeable lithium air batteries (LABs) are often considered as one of the most encouraging conversion and storage devices for implementation in future electronics. However, in spite of a large number of studies been performed in the last few decades toward development of LABs, they have still not been found fit for commercialization, as practical energy storage devices, mainly because of issues related to the cathode materials. In fact, the oxygen reduction reaction (ORR) that takes place in the air cathode has been found to be a vital factor influencing the performance of LABs. Keeping this in mind, fundamentals of ORR, as well as the recent progress made in the development of cathode materials, have been emphasized this chapter. In addition, insights on future research directions in terms of overcoming the challenges and commercial viability of LABs have also been provided.