St. Mary’s Healthcare System for Children, one of the nation’s leading pediatric post-acute care institutions, has announced a significant leadership transition.
The Board of Directors proudly revealed that Sean Lally has been appointed as the next President and Chief Executive Officer, succeeding Dr. Edwin Simpser, who will retire at the end of June after dedicating over 25 years to the organization.
Lally’s appointment follows a comprehensive, nationwide search and comes at a pivotal time in St. Mary’s storied legacy. For more than 150 years, the organization has provided care to New York’s most medically fragile children, becoming the state’s largest provider of long-term care for children with complex medical conditions.
“This is an exciting new chapter for St. Mary’s,” said Cindy Johnson and Stephen Brent Wells, Co-Chairs of the Board of Directors.
“Sean is a trusted leader who deeply understands our mission and shares our strong unwavering commitment to building a brighter, healthier future for children with medical complexity. Together with our dedicated St. Mary’s team, he will help lead us forward with vision, compassion, and continued innovation in delivering extraordinary care. The entire St. Mary’s community is filled with optimism and excitement.”

Lally brings with him nearly a decade of internal leadership experience at St. Mary’s, currently serving as Executive Vice President and Chief Strategy Officer. In that role, he has led the organization’s strategic planning initiatives, overseen operations management, and been responsible for system quality and improvement.
He has also directed fundraising efforts and managed external relations activities. His contributions have been instrumental in shaping the organization’s path forward.
In addition to his work at St. Mary’s, Lally’s career includes leadership roles at prominent institutions such as Memorial Sloan-Kettering Cancer Center, the American Museum of Natural History, and the New York Historical Society. His diverse background and strategic expertise position him well to guide St. Mary’s through the challenges and opportunities of the evolving healthcare landscape.
“I am humbled and honored to have the opportunity to succeed Dr. Simpser and lead St. Mary’s forward into its next chapter where we will continue to deliver on our mission and provide the absolute best care for our unique patients while setting the Healthcare System up for long-term success,” said Lally.
“There is truly no place like St. Mary’s for medically complex children and their families – a testament to our Board, our incredible doctors, nurses, therapists and other staff who I look forward to continuing to work with for years to come.”
Dr. Edwin Simpser leaves behind an extraordinary legacy of leadership and innovation. During his tenure, St. Mary’s launched numerous groundbreaking programs for children with special needs, including the St. Mary’s Center for Pediatric Feeding Disorders, state-of-the-art rehabilitation and locomotor programs, and St. Mary’s Home Care.
“It has been the honor of a lifetime to serve St. Mary’s for more than twenty-five years as both Chief Executive Officer and Chief Medical Officer, but it is time for me to pass the torch. I am incredibly proud of all that we have accomplished together as an organization in serving children with complex medical conditions,” said Dr. Simpser.
“I would like to congratulate Sean, and I know that he will lead the organization to new heights while managing the challenges of New York’s healthcare landscape.”
St. Mary’s is located at 29-01 216th St. in Bayside. For more information about its programs and services, visit stmaryskids.org.