The Chief Medical Officer, Dr Tony Holohan, is to step down from his role.
He has been appointed as Professor of Public Health Strategy and Leadership at Trinity College Dublin. (TCD).
Dr Holohan will take up this new position on July 1st.
He has held the post of Chief Medical Officer in the Department of Health for 14 years.
Taoiseach Micheál Martin has led tributes to Dr Holohan for "more than two decades of outstanding and dedicated service to the people of Ireland".
"His steadfast assured advice, and willingness to communicate over the course of the COVID-19 pandemic undoubtedly helped saved lives, and kept Ireland safe during an exceptionally challenging two years," Mr Martin says.
The Taoiseach says Dr Holohan provided "the assurance we needed" during the COVID-19 pandemic.
"I have known Tony, and had the privilege to work with him, since he was appointed Deputy Chief Medical Officer in 2001, and then during his 14 years as the Chief Medical Officer.
"His work chairing the NPHET, his professionalism, and calm and personable nature gave us all the assurance we needed during the pandemic.
"In parallel, Tony worked consistently to raise and transform the profile and status of public health medicine, and worked hard on creating a professional pathway to consultant status."
Health Minister Stephen Donnelly says Dr Holohan "made a huge and lasting impact on health in Ireland."
"Throughout the pandemic his advice to Government has shaped our response to Covid and I witnessed first-hand his unwavering dedication", he tweeted.
Since his appointment as Chief Medical Officer in 2008, Dr Holohan has made a huge and lasting impact on health in Ireland. Throughout the pandemic his advice to Government has shaped our response to Covid and I witnessed first-hand his unwavering dedication.
— Stephen Donnelly (@DonnellyStephen) March 25, 2022
Trinity College Provost Linda Doyle says: "Dr Holohan has become a household name for his service to the country over the past two years but there is plenty that still needs to be done to protect Ireland from future pandemics.
"We’re excited that he will be working with other academic colleagues in Trinity to learn the lessons of COVID and prepare for these future challenges."
Dr Holohan says: "It has been a great privilege for me to serve as Chief Medical Officer and to have had an opportunity to be directly involved in issues of great importance and relevance to the health of the people of Ireland.
"In particular, these past two years have presented extreme challenges to public health globally and I have been honoured to work alongside exceptional colleagues in the Department of Health, the HSE, the wider health service and across Government.
"During this time, I have witnessed the dedication of colleagues to protecting the health and wellbeing of people across Ireland."
He adds: "I am very excited by this new opportunity, and I look forward with energy and enthusiasm to working with the Provost of Trinity College Dublin and her team"
Dr Holohan will not be attached to a single school or discipline at Trinity.
Instead, the university says his role will traverse the Faculties of Arts Humanities and Social Sciences and Health Sciences, "recognising the complexity and scope of population health challenges in the modern era".
Dr Holohan stepped aside from his role for a time in July 2020, revealing his wife Emer was receiving palliative care.
Deputy Chief Medical Officer Dr Ronan Glynn was appointed Acting Chief Medical Officer for several months before Dr Holohan's return.