Len Fishman will retire next spring after a dozen years as chief executive of Hebrew SeniorLife, a Harvard-affiliated provider of senior health care and housing.

Taking his place will be the organization’s president, Lou Woolf, a former North Shore Medical Center executive who has been with Hebrew SeniorLife since 2009.

Earlier this month, it signed a preferred provider agreement with Boston’s Beth Israel Deaconess Medical Center, with which it has had a 60-year clinical affiliation.

In a statement, Hebrew SeniorLife board chair Jennifer Silver credited Fishman with expanding the organization’s role as a national leader in geriatric research and teaching.

“Len’s leadership broadened HSL’s scope from a long-term care organization to an integrated health care and housing system, serving seniors of all faiths and incomes, increasingly in community-based settings,” Silver said.