Components such as gears, bearings, and shafts are essential to effective automation, ensuring reliable, cost-effective design. Actuators such as DC, AC, and stepping motors are equally important to automation. Studies in mechatronics make equal use of both gears and actuators in the practical construction of automated equipment. This special issue on gears and actuators looks at studies on load bearing capacity in mechanical system design, including micropitting generation and high-speed finishing of hard gear teeth for garnering insights into mechanisms behind successful automation. It also monitors the study of trajectory planning and motion control of robots using ball screws, worm gears, stepping motors, and AC motors. Our deep appreciation goes to the authors for their informative and interesting papers and to the editors for their generous time and effort in making this special issue possible.