For almost its entire existence, Southwest Airlines has been an all-Boeing 737 operator. With a single aircraft type in its fleet, the carrier has been able to offer a low-cost product, consistency, and a simplified operation. As one of the world's largest 737 Next Generation (NG) operators, it was clear that the airline would take an interest in the NG’s successor: the 737 MAX. Becoming the first US carrier to operate the MAX 8, Southwest took delivery of its first plane in 2017.