It comes after Matt O'Connor, who founded the group in 2001 and has also founded a PR agency, decided in September last year to devote himself full-time to the campaign.
He told PRWeek the group is also looking for an Irish agency.
While Fathers4Justice (F4J) is best known for eye-catching stunts (below) to highlight what it says are legal disadvantages for fathers of separated families, O'Connor said it had evolved over time. While legal issues remain its core issue, it now also focuses on the mental health issues and suicide that can result from family breakdown.
This evolution has included its #ForgottenFathers media relations campaign in Scotland, which gained front-page coverage and engagement from several MSPs. O'Connor praised newly hired agency Orbit for having turned this work around "extraordinarily quickly".
"We’re obviously known for scaling buildings, but we wanted to do something a bit more engaging, a bit more sensitive," he told PRWeek.
Fathers4Justice has now taken on Taylor Herring to manage a UK-wide campaign. O'Connor declined to elaborate on what the independent agency would be launching, but said that the group still wanted to be "innovative and creative".
O'Connor said he had also been in discussions with several Irish PR firms, but was yet to find one that was a good fit. "We need to find an agency who is really going to get on board with the ethos of the campaign," he said.
F4J had a "soft launch" in Ireland last year, and also began doing some work in the US - including a stunt after the separation of actors Angelina Jolie and Brad Pitt.
O'Connor's wife Nadine leads the US and Irish work, with the American operation having been given some office space by a beneficiary in Boston.
"There has been a big shift in the US in the approach to family breakdown, and there is now a presumption of shared parenting in many states; it’s a real sea change," O'Connor said, arguing that the US was a long way ahead of the UK in its attitude to the rights of divorced fathers.
The O'Connors have two full-time staff working for the campaign, and two other volunteers based in their London office. Other volunteers also provide support when needed.
The organisation is "entirely self-funding", O'Connor said, receiving no grants or state funding. Fathers (or others) looking for support can register through the website, at a cost of £30 a year, for a confidential online help forum. Lifetime supporters pay £600 and are given telephone support. F4J also has an online shop, and asks for donations via the website.
Prior to taking the step of going full-time in September, O'Connor had founded an agency called Agitator Consultancy. He had previously created experimental ice-cream brand The Icecreamists, during which time he worked with Taylor Herring, including on a PR stunt where he created a breast milk ice cream.
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