Monica Valdes Lupi has worn several hats in Boston’s health department, but now the 42-year-old policy specialist is poised to become its leader.

The board of the Boston Public Health Commission on Wednesday is scheduled to vote on Valdes Lupi’s appointment as executive director, with the blessing of Mayor Martin J. Walsh.

Valdes Lupi will oversee an agency that touches nearly every segment of life in the city, from programs that help children and families to initiatives that tackle infectious diseases, addiction, homelessness, and emergency medical services.

Valdes Lupi has “exceptional experience at the forefront of public health policy and a proven record of coordinating and implementing important public health initiatives,’’ Walsh said in a statement. “I have no doubt that her local, state, and national experience will enable her to solve the most pressing public health challenges facing our city.’’

A search committee spent the past year reviewing candidates and chose Valdes Lupi, with members noting her 20 years of experience in public health initiatives, much of that in Massachusetts.

Valdes Lupi served as senior health policy manager and later chief of staff for the health commission, from 2001 to 2007, according to the agency.

She then served as chief of staff and deputy commissioner at the state health department. While there, she helped lead the day-to-day operations of an agency with 3,100 employees, according to Valdes Lupi’s resume.

Most recently, she has worked as a chief program officer at the Association of State and Territorial Health Officials, a trade association that represents public health agencies.

Valdes Lupi received a law degree from the Dickinson School of Law and a master’s degree in public health from the Boston University School of Public Health.

The health commission board has not yet set the salary for its new director, but the previous chief executive, Barbara Ferrer, was paid $153,661, according to a commission spokeswoman.

Kay Lazar can be reached at Kay.Lazar@globe.com Follow her on Twitter @GlobeKayLazar.