Instead of running an ad about Microloan, our ‘Women 4 Women’ campaign sold free media as advertising space to UK businesswomen, with all donations going to other businesswomen in Africa.

Rather than use the traditional charity model of spreading the net wide to generate mass awareness and thus maximise donations, we did the opposite by micro-targeting those most likely to donate and give them something that was otherwise unattainable – a personalised poster and the opportunity to buy a single site poster within one of the world’s busiest transport systems.

The idea had shifted from advertising the brand of MicroLoan to selling a complete advertising package for ‘your’ small business on the London Underground.

What started as a simple poster became a multi-channel campaign. We had to make the entire package incredibly appealing to our savvy businesswoman.

First, we created an online film to explain the idea and distributed it to digital influencers; from design blogs to business websites.

Secondly, the final poster design had to be visually striking enough to stand out in the Underground, yet be simple enough to design and produce for dozens of different businesses within a short period of time. We created a flexible style guide that ensured all of the posters worked together, yet allowed each individual business to communicate their own unique selling point.

In the end, over 80 pieces of work were designed, produced and distributed to 2 very distinct target audiences: the business owners who needed to buy a poster, and the final commuters who would see the final advertising campaign.

• Donations: We sold all 200 posters to a total of 82 businesses in the first week. This raised £20,000 before the posters even went live, a hefty increase from the previous poster campaign that only managed to raise £55.50.

• People helped: While £20,000 seems tiny, this goes a long way in Africa, with the average loan just £72, meaning we were able to give a hand-up to nearly 300 African businesswomen.

• New recruits: Of the 83 donor businesses only 10 of these had been involved with MicroLoan previously, meaning 88% of our donors were new to the brand.

• Talkability: Through the poster-finding exercise #SeeAPosterHelpABusiness activity on Twitter, both the campaign and the brand were exposed to the multiple audiences of each business. We also gained pick-up on creative industry sites, even getting Ad of the Week on The Drum, further extending the reach of the campaign.