Mobile phone mast protesters from across London have met to pool their campaign ideas.
National group Mast Sanity, which has organised the event, is also hoping to set up a London branch to help co-ordinate local protest groups.
Karen Barratt, of Mast Sanity, said a focus is needed as there are dozens of campaigners across London.
She said: "We have to pull together to tackle the problem of mast siting which is out of control."
The meeting took place at the Royal Festival Hall on London's South Bank between 1200 BST and 1500 BST on Saturday.
Ms Barratt explained that the problem is more acute in London as everything is a lot closer together.
"There are much less open green spaces and so there are large number of masts close to schools and populations," she said.