The Isle of Man Harbours & Coastguard has signed a memorandum of understanding with the RNLI.
It's hoped the move will "build on a positive relationship" and enable both parties to continue their life-saving work.
The new document lays out each organisation’s responsibilities for search and rescue operations on the island.
The Coastguard is responsible for tasking and coordination of operations while the RNLI provides substantial resources towards saving lives at sea with lifeboats and volunteer crew.
John Payne from the RNLI said: "The RNLI has a long and proud history on the island, with Douglas being the birth-place of the RNLI, so it’s fitting that this document was signed here.
"We are pleased to officially recognise this relationship with a Memorandum of Understanding between us".
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