Dr David Hogan, a GP at Hadleigh Practice in Broadstone, was elected by the board last Friday.
Dr Hogan said: “Castleman is in a great place to keep helping shape healthcare in Dorset and beyond.
“We have a brilliant team and strong values like honesty and fairness.
“I’m really looking forward to working together to keep improving care for patients.”
Dr Christina Hawkins will continue as vice chairman and James Leyland has been reappointed as director of HR.
This leadership team aims to uphold high-quality, community-based healthcare.
Castleman Healthcare recently celebrated 10 years of supporting general practice across Dorset.
Formed by 12 member practices, it has grown into a trusted organisation that helps surgeries work together, improves care and eases pressure on healthcare services.
It supports GP practices in Crane Valley, Poole North and Wimborne and Ferndown and runs specialist diabetes clinics, supports older people with frailty and provides training and coaching for healthcare staff.
Fiona Cleary, CEO, said: “We’re proud to have such a strong, committed leadership team.
“With this team in place, we’re ready to take on the next decade of care.”