The top Marine is headed into his fourth and final year as commandant of the Marine Corps, which means the torch will be passed to a new leader to continue the Corps’ modernization in 2019.

Gen. Robert B. Neller was confirmed by the Senate as the 37th commandant in August 2015, and since then, the four-star infantry officer has been on a sprint to prepare the Corps for a bout with rising adversaries.

He has overseen an overhaul of grunts with new tech, automatic weapons, grenade and rocket launchers, and is still toying over a decision to possibly boost the rifle squad to 15 Marines.

He has also continued efforts to integrate women into previously closed combat jobs fields and established a task force to help reshape the Corps’ culture in the wake of the Marines United nude photo sharing scandal.

The next commandant will preside over a series of new challenges from developing Marine Corps cyber, continuing gender integration and modernizing the force, while dealing with a dwindling recruitment pool.

Where will Neller go next?

It’s unknown what’s next for the 37th commandant, but at a Brookings Institution discussion in April, he told Ret. Marine Gen. John Allen that if he retired from active service, he would build a house in Texas, ref high school football, and work on his golf game.