Jimy Williams embarked on his baseball journey as a player before transitioning into a managerial and coaching role. His career began in the minor leagues, where he played as an infielder. Williams spent several years honing his skills on the field, playing for various minor league teams within the Boston Red Sox organization. Although he never made it to the major leagues as a player, his understanding of the game and leadership qualities paved the way for his future roles in baseball management.

Williams transitioned into coaching, starting as a minor league manager in the Red Sox system. His managerial career in the minors was marked by a keen ability to develop young talent and a strategic approach to the game. This experience laid the groundwork for his eventual promotion to the major leagues, where he served as a coach for the Toronto Blue Jays. During his time with the Blue Jays, Williams was part of the coaching staff that helped guide the team to its first American League East title in 1985.

In 1986, Williams took on the role of manager for the Toronto Blue Jays. His tenure as manager was marked by a focus on discipline and fundamentals, which helped the team remain competitive in the American League. However, his time with the Blue Jays was relatively short-lived, as he was replaced midway through the 1989 season.

Williams continued his career in baseball by joining the Atlanta Braves as a third base coach. His time with the Braves was a period of growth and learning, as he worked under the guidance of renowned manager Bobby Cox. The Braves experienced significant success during this era, and Williams was part of the coaching staff that contributed to the team's achievements.

In 1997, Williams was appointed as the manager of the Boston Red Sox. His leadership style and strategic mindset helped the Red Sox secure a playoff berth in 1998, marking the team's first postseason appearance since 1995. Williams' tenure with the Red Sox was characterized by his ability to manage a diverse roster and navigate the challenges of a competitive division. However, he was dismissed from his managerial role in 2001, midway through the season.

Williams' career continued as he joined the Houston Astros as a bench coach. His experience and knowledge of the game were valuable assets to the Astros' coaching staff. In 2002, he was promoted to the position of manager, where he led the team to a second-place finish in the National League Central division. Williams managed the Astros until 2004, when he was replaced during the season.

Throughout his career, Jimy Williams was known for his strategic approach to the game and his ability to develop and manage talent.