Why I leave hidden messages in High Street clothes

All her life Sarah Corbett has been a campaigner for causes she believes in, but in her mid-20s she had had enough of carrying banners and shouting. She decided to take a gentler approach and became a craftivist - using handicrafts to send a message.

I'm standing with Corbett in a central London clothes shop famous for its fast fashion - and frequently accused of buying from sweatshops - watching her slip tiny handmade scrolls into PVC macs.

In delicate swirly writing, each scroll reads: "Clothes maketh the person" - that's quite a responsibility, isn't it?

Sarah works quickly, pretending to scrutinise the garments before depositing a scroll from the deep pockets of her trenchcoat. It makes her nervous - she doesn't get a buzz from it. But she's doing it anyway.

This clandestine "shop-drop" is the just the latest escapade in a lifetime of activism. She was just 16 when she organised her first campaign, to get lockers installed for the pupils at her school.

The head teacher told her it wasn't possible on "health and safety grounds".

"I was dubious so I asked the caretaker, Mr Gilbert, if it was a health and safety issue and he looked confused," Corbett remembers. "We spent some break times quietly together measuring the rooms and corridors and found out that it was not a health and safety issue."

Next, she and an influential parent governor put the idea to the teachers and other governors - and this led to lockers that are still being used by students today, 17 years later.

"What it taught me about campaigning was that to 'win' a campaign you didn't have to protest publicly like a performance, you don't always need petitions signed," she says. "It made me see campaigning as much broader and creative than we often think."

Her next campaign was against gym knickers, which she and many other girls at the school - in an area of Everton known for prostitutes and kerb crawlers - detested.

"Running around the outdoor grounds in gym knickers felt exposing, degrading and we would see men in cars parked up watching us," she says.

"We lost that fight because one PE Teacher was extremely stubborn and refused to meet to discuss the issue and was very intimidating. I wish I had had more courage to work around her, mobilising the students and governors, but I was scared of that teacher. I learned a lot from both campaigns."

It's no surprise, perhaps, that Corbett later became a professional campaigner for charities such as Oxfam and Christian Aid, as well as an activist for other causes.

But by the time she reached her mid-20s she felt burnt out.

"As an introvert most activism drained me of energy, whereas my extroverted sister gained energy from the same activism actions such as going on marches chanting, taking part in demonstrations outside embassies and businesses, sometime dressing up and acting or performing in costumes and asking people to sign our petitions."

During a Lovebox festival in London, where Sarah's role was to get as many people as possible to sign a climate justice petition, she found herself standing in a Portaloo.

"I thought, what am I doing? I'm hiding in a smelly festival toilet so that I don't have to talk to people about global warming and so colleagues don't see me slacking."

The result of that moment of crisis in a Portaloo was the Craftivist Collective - a social enterprise, founded by Corbett to encourage people to combine craft with activism for social justice causes. The shop-drop I witness in the London clothes shop, is a quintessentially craftivist act.

Each of the delicate scrolls is neatly written on embossed paper and tied up with a colourful bow. They say "please open me" rather than OPEN ME NOW.

"They are designed to encourage people to be curious about who made their clothes," Corbett says. "It is about provoking questions in a gentle way, rather than preaching."

The term "craftivism" was first made popular by US writer and crafter Betsy Greer in 2003, and the movement has steadily gained momentum since then. The "pussy hats" knitted for the women's march a day after Donald Trump's inauguration are a famous example of the craftivist's art - combined in this case with a conventional street protest.

Craftivism is not meant to replace conventional forms of activism entirely, she says, just add another tool to the toolkit.

The Craftivist Collective has recently collaborated with the mental health charity, Mind, to make craft kits that help people to stitch a letter to their MP, reminding them not to cut funding for mental health services. The hope is that the letters will be embellished with decorations to make them beautiful - the kind of thing an MP might want to put on display, rather than just another manila envelope or angry email.

It's the ultimate non-threatening action, and this is entirely deliberate.

"In every other area of life we know that demonising people, shouting at people, guilt-tripping people, shaming people, doesn't work," says Corbett, who has just published a book, How to be a Craftivist: the Art of Gentle Protest .

"But gentle protest doesn't mean weak or passive. You can use something that is kitsch and colourful to challenge people with quite strong messages - it is disarming."

Sparking intrigue is often a big part of Corbett's strategy - with the scrolls, for example. Her messages may need to be found - they're usually hidden away or placed somewhere that isn't at eye level.

A few years ago, Sarah affixed a mini-banner to the bottom of a fence around a basketball pitch - a hang-out for young men, in a part of South London notorious for gang violence.

On it was stitched a quotation from the film director, Martin Scorsese: "It seems to me that any sensible person must see that violence does not change the world, and if it does, then only temporarily."

She hoped the kids would notice it, find it surprising and understand that someone cared about them.

Corbett and Grenfell

Corbett and her family lived on the 14th storey of a tower block, which used to sway in the wind to the point where water would slosh out of the toilet bowl. "The lift was often broken and small fires would happen," she says. It was this that propelled her mother into local politics.

"My mum asked the firefighters what to do if a fire happened and they said they had ladders up to the 10th floor. When she said that we lived on the 14th floor they had no answer to give her.," Corbett says.

"When Grenfell happened I called my mum and we both got really upset and angry that something like that could still happen. I still get so angry and emotional thinking about it."

Only 33, it's already 30 years since she first stood on a picket line with her parents - a vicar and a local politician - to protest against the demolition of social housing near their home.

She grew up with mugs bearing messages such as Free Nelson Mandela, or Coal not Dole.

In some ways she's already a veteran of the activist world, one who has spent many years finding her own distinctive voice.

"I hope people don't find it smug or passive-aggressive, I've worked really hard on sending the right message and I hope people are excited about finding them," says Corbett. "I think craftivism can engage people in a transformative and respectful way - it plants a seed in people's minds."

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