The papers in this special section on emerging multiport electrical machines and systems is to provide an opportunity for researchers and engineers from academia and/or industry, to exchange their enlightening ideas on analysis, design, and control of such new machine breeds, to identify the challenges in practical applications and to present the state-of-the-art solutions. Distinct from the conventional electric machines with only one electrical and one mechanical port, electrical machines featuring multiple electrical/mechanical ports provide a highly efficient, compact, and flexible manner to convert and/or transfer energies among different ports. The additional electrical ports can be used to increase the power rating, enhance the fault-tolerant capability, and control the motion/power flow. The extended mechanical ports are commonly used to decouple the motion, speeds, and/or torque. The multiport feature opens a new era in traditional electric machinery and provides an effective approach to the application-oriented design of new energy conversion systems. Though relatively young, they have experienced rapid developments in terms of available topologies, analysis and design techniques, and control strategies in a wide range of applications, such as electric vehicle/hybrid electric vehicles, high power industrial drives, rail transportation, wind turbine systems, ac–dc microgrids, more electric aircrafts, and so on, during the past decades.