Like most good ideas, the realisation that the world was in need of a Fashion Revolution came to Carry Somers while she was sitting in the bath.
She was having soak after a stressful day on 24 April 2013 - the day of the Rana Plaza factory collapse in Bangladesh.
As a sustainable fashion advocate and the founder of Pachacuti - a accessories brand dedicated to using environmentally friendly materials and Fair Trade production - Somers was particularly disturbed by the events that killed 1,134 people.
"It was a feeling of shock, but also an awful feeling of inevitability," she tells HuffPost UK Lifestyle. "We knew something like this could happen. Many, many smaller disasters had happened, but they just hadn’t had the media coverage."
With the world's media focussing on the disaster and public outrage at the conditions of factory workers at an all-time high, Somers knew it was the right time to start a new campaign fighting for a more ethical and sustainable fashion industry.
She dried herself off, called her good friend Orsola de Castro, and the pair immediately began making plans to co-found Fashion Revolution Day.
Fashion Revolution Day happens once a year on the anniversary of the Rana Plaza disaster.
It's aim is simple: To get people asking where and how their clothes are made and to highlight the wider impact that has on the environment and society.
"Fashion Revolution Day is not meant to be a new movement, but a way of bringing together all the people who are already calling for change," Somers says.
"I want to give a platform to all those voices in order to make one voice that's louder and more likely to lead to change."
Somers sent emails to key figures in the industry explaining her idea, from journalists to staff at London College of Fashion, and was pleasantly surprised when "everybody wanted to be part of it".
Now on 24 April each year, members of the public take selfies showing the labels on their clothes. They tag the brand and ask #whomademyclothes? in order to promote transparency in the industry and raise public awareness of ethical fashion.
"What we’re trying to say is, as consumers, we do have incredible power to make a change," explains Somers.
"And we really should be using that power we’ve got, not to be boycotting, but by saying to brands: 'We want to buy your clothes, but we also want you to be accountable.'"
This social media movement isn't meant to purely tackle cheaper brands more commonly associated with fast fashion. Somers says a revolution is needed across the industry, including among high-end brands.
"So many brands following the Rana Plaza collapse genuinely didn’t even know whether or not they were producing in that factory complex," she says.
"The luxury brands don’t necessarily know where their clothes are coming from. Just because something has a major name, it doesn't necessarily mean the production took place in Italy.
"A lot of the luxury brands are made following similar supply chains and are on the same production lines as fast fashion."
Unfortunately, Somers isn't exaggerating the severity of the situation.
The Behind the Barcode Fashion Report published to coincide with Fashion Revolution Day last year found that 48% of brands hadn’t traced the factories where their garments were made.
What's more, 91% of brands didn’t know where their raw materials came from.
Conditions for garment workers in some of the factories we do know about can be dire.
Ilana Winterstein, a director at Labour Behind The Label previously told HuffPost UK Lifestyle the workers, who are mostly women, often suffer "poor health, are victims of sexual and physical abuse and cannot afford to send their children to school."
Somers has even met women struggling to make clothes while living in refugee camps.
As well as raising public awareness, Fashion Revolution Day is about re-establishing the broken connections in the supply chain because "greater transparency is a prerequisite to improving conditions".
Somers believes we need to see transparency "in policy and in practice, not just in principle", and while consumers putting pressure on brands to run ethically and sustainably will make a difference, she feels that alone is not enough.
"In order to see that people are working in decent conditions and receiving a living wage there has to be involvement from the Government," she adds.
Fashion Revolution is no longer about one day in April.
Since starting the movement in 2013, Somers has organised debates at the House of Commons and the House of Lords on transparency and sustainability in the fashion supply chain and hosted Fashion Question Time in the Houses of Parliament.
And it seems the efforts of her and her team are working.
Fashion Revolution Day is now recognised in 79 countries around the world. The global reach from Fashion Revolution Day 2015 was estimated to be a whopping 16.5 billion from online and broadcast media, with news outlets from the BBC to CNN covering the day.
"We are really incredibly surprised at how quickly the movement has grown," Somers says.
"I think it tapped into the fact that people felt powerless - everyone knew that there needed to be a better way, but I think what the first Fashion Revolution did was give consumers very tangible, accessible tools to make a difference."
Having said that, the Fashion Revolution team are not about to rest on their laurels.
They'll be launching a living wage campaign next year and are currently working on a a transparency index.
"The index will give people a chance to get the key facts about major brands, by rating brands in terms of their transparency," Somers explains.
"Traceability is a key part of it. We'll disclose whether or not brands publish their first tier, second tier and further factories and whether they have anything available like a factory map.
"With H&M, for instance, you can now see their factories on a map on their website."
Despite the fact that big names including Mary Portas, Livia Firth and Katharine Hamnett have shown their support for Fashion Revolution Day, above all else, Somers wants to ensure sustainable and ethical fashion doesn't becoming a passing trend.
"Sustainable fashion can't become 'fashionable', ithas got to become the norm," she says.
"There is no alternative because there isn’t a future for fashion without it being sustainable. Our planet cannot support an unsustainable industry.
"Sustainable fashion has got to become simply 'fashion'."