The ITER ion cyclotron heating and current drive system is designed to deliver 20 MW to a broad range of plasma scenarios, during very long pulses (∼500 s in inductive, up to 1 h in noninductive, plasma scenarios). The associated radio-frequency (rf) source system has to be compliant with all operation modes foreseen in ITER operation. India is responsible for delivering the rf source package to ITER, which includes one prototype rf source followed by eight bulk production units. This lecture presents the ITER rf source system, design considerations, and status of the research and development program to identify and resolve the major technological challenges involved.