5G multiple access, and the physical layer in general, has differences from Long Term Evolution (LTE). This chapter presents the 5G physical layer principles, including the mapping of the transport channel to the physical channel, 5G frame structure, and key physical layer procedures. Special emphasis is on the new features compared to LTE, such as full support of beamforming, larger bandwidths, and a more flexible frame structure. The chapter also introduces the 5G channel coding solutions, physical layer procedures, and measurements as specified in 3GPP. One of the key enablers for beamforming is the sweeping sub-frame. Random access with 5G supports different PRACH formats and numerologies to cope with different deployments. The user data in the downlink direction is carried on the PDSCH. The chapter concludes with an overview of the physical layer aspects of the 5G UE capabilities.