Leo McGarry is a fictional character from the television series The West Wing, portrayed by actor John Spencer. He serves as the White House Chief of Staff under President Josiah Bartlet, playing a crucial role in managing the administration's operations and strategy. Leo is known for his strong leadership skills, loyalty, and dedication to public service. Throughout the series, Leo faces personal challenges, including struggles with alcoholism, which add depth to his character. His relationships with other key characters, such as C.J. Cregg and Toby Ziegler, highlight his mentorship and support within the White House team. Leo's character is often seen as a moral compass for the administration.