Formerly the deputy chief, 49 year old Gary Roberts becomes the first Island officer to take the helm.
Mr Roberts started as a constable in Douglas 28 years ago and rose through the ranks.
His predecessor Mike Langdon fostered a neighbourhood policing approach which has seen crime in the Island fall to the lowest level of any British Isles police force.
Chief Constable Roberts is committed to sustaining that policy - if funds allow:
Teenager made 'knuckleduster' on way to fatal fight
Witness accused of lying to police following friend's death
Jenkins v Thomas in battle for the top job
MHKs will pick the new chief minister next Tuesday
Two candidates to compete for chief minister position
Chris Thomas and Kirrie Jenkins to stand for the top job
Tributes paid to Douglas' Smudge the Cat
The owners of the city's favourite feline has confirmed her death