In recent years, scientists at DIII-D have solved a number of key physics problems for practical fusion power, including
Techniques to limit and mitigate conditions that could damage the reactor (control of edge-localized mode, disruptions)
Techniques for maintaining the fusion plasma for extended periods of time (steady-state operation)
Development of operating scenarios for ITER - the multinational fusion experiment that aims to demonstrate net gain
Find more details of the DIII-D Research Program at https://fusion.gat.com/global/diii-d/home.