A celebration of life is planned Sunday at UMass Boston to remember Phil Johnston, a veteran consultant who served in the Legislature and in top state and federal health and human services posts.

Johnston, 80, died unexpectedly on Saturday, April 5.

A graduate of the University of Massachusetts Amherst, Johnston was a state representative for eight years in the 1970s and 1980s before he joined Gov. Michael Dukakis’ team as health and human services secretary.

“He was a public servant to his core who was relentlessly committed to improving the health and wellbeing of children and families in Massachusetts and across the country,” said Gov. Maura Healey. ” He was also a great friend who could always be counted on to provide insightful advice.”

In the 1990s, Johnston was regional health and human services secretary under President Bill Clinton. He nearly won election to the U.S. House in 1996 but was edged in a close Democratic primary race by William Delahunt.

Johnston chaired the Massachusetts Democratic Party from 2000 until 2007 and owned Johnston Associates for nearly 30 years. He chaired the Massachusetts Health Policy Forum for more than 28 years, and chaired the Robert F. Kennedy Center for Justice and Human Rights for five years ending in 2010.

An initial list of speakers at Sunday’s event includes U.S. Sen. Edward Markey; Rev. Ray Hammond, co-founder and pastor of Bethel A.M.E.; Kerry Kennedy, president of Robert F. Kennedy Human Rights; former Congressman Joe Kennedy III, and former CEO of Blue Cross Blue Shield of Massachusetts Andrew Dreyfus.

The three-hour event begins at 1 p.m. at the UMass Boston Campus Center Ballroom and Terrace.