If you speak to any business leader on sustainability these days, what's uppermost on their minds is the issue of scaling up.

While Apple's iPad, for example, quickly transformed the market for computers, why are innovations in sustainability failing to reach scale, even when they have proved their worth?

The Better Cotton Initiative, which is backed by companies such as Levi Strauss, Marks & Spencer, IKEA, H&M and Adidas, believes it can transform the textile market and make it more sustainable. If they are proved right, it would have a marked impact not only because cotton is used in 40% of all global textiles, but also that 300 million farmers in 80 countries rely on it for their livelihoods.

The BCI is taking a top down and bottom up approach. While the consortium of apparel companies put pressure on their supply chain to guarantee a market for 'better' cotton, the BCI also works in partnership with NGOs, such as the Solidaridad Foundation, to train farmers to meet that demand.

But unlike programmes such as Fairtrade, there is no formal product labelling system for consumers and no premium paid to the farmers. This may lead to accusations that the apparel companies are trying to have their cake and eat it, by proving their sustainability credentials while keeping farmers in poverty.

But such accusations won't be fair. Michael Kobori, head of Levi's global sustainability programme, says that by taking out the need for labelling, the consortium's cotton can flow into the entire supply chain rather than being limited to clothes that can prove they are 100% BCI certified. By not paying extra to the farmers, there is a much higher chance of the initiative reaching scale because it will not be hemmed in by being seen as a niche premium product.

But how do the farmers benefit? The scheme is coming to the end of its second growing season, and the training farmers have received has already been shown to lead to a significant reduction in the use of pesticides and increased profits, since chemicals can account for up to 60% of farming costs.

Cotton growing also demands huge amounts of water and the BCI model has seen significant reductions in irrigation needs.

Keith Tyrell, director of Pesticide Action Network UK, says: "Smallholder farmers get very little training in using pesticides and tend to spray their crops far too often. They also lack knowledge of the hazards around them. There are still instances in Africa where farmers are doing tongue testing to assess the right concentration of pesticides. The initiative helps them to understand their crops and pests and give them the ability to do more with less."

This has reduced pesticide use in developing countries. Tyrell also points to a 40% reduction in water in case studies in Pakistan and how farmers in the Punjab in India have been encouraged to switch from flood irrigation to drip irrigation.

M&S is funding a BCI project with WWF in India and its first harvest has shown an 80% reduction in pesticides and cut water usage by half.

So if it's such a great idea, will it catch-on in the same way the iPad transformed the market for computers? Unfortunately, the answer is likely to be no.

The analogy with Apple is unfair in many regards, but it serves to prove a point. The iPad's proof of concept was all done in its labs, Apple was in control of its supply chain, the product was exciting and captured consumers' imagination, and it has the power of Apple's finances and brand prowess behind it. Plus, of course, Apple sees it as the next evolution of its market dominance and therefore central to its strategy.

The BCI has none of these advantages. It is having to show proof of concept in the field, which takes time, and it has little control over the supply chain, given the global nature of the commodity. So far it has engaged 100,000 farmers in four countries, which is a fair start, but itwill struggle to meet the demands of the retailers who have already signed up. "We do not want to ramp up demand hugely before we can guarantee a reliable supply," Kobori says.

Lack of funding for expansion also poses a problem. While the retailers are putting in some seed corn funding, matched by the Dutch government, it is not nearly enough to support a major scale-up.

BCI's corporate backers do not have a direct and immediate economic benefit from the scheme. The farmers in the M&S India project, for example, have no requirement to sell to them. So while in general terms, they want to secure production of cotton and prevent farmers from switching to other crops, they are unlikely to pay considerable amounts of money into a scheme that may well benefit competitors at their expense.

One way around this is to sign up new members to the consortium but this is also facing difficulties. The Gap retail empire was a founder member but pulled out in the early stages and attempts to bring it back on board have failed.

There are also issues with the supply chain. Mark Sumner, a sustainable raw materials specialist at M&S, says: "It's a very disparate industry and it is hard to work out where the cotton is coming from, so it's difficult to unpick and influence.

"Also many mills have been reluctant to hand over information about their suppliers for reasons of confidentiality and fearing who we will hand it over to. It takes a while for them to understand how everyone can benefit from the initiative."

BCI, though, can show some success. Lise Melvin, executive director, says the second harvest in India and Pakistan has yielded 100,000 tonnes of cotton, which compares to Fairtrade which at its peak secured around 35,000 tonnes and the organic label which yielded 175,000 tonnes. But the figures must be set against the annual global production of more than 25 million tonnes.

BCI is also different to traditional NGO-led food security programmes. It involves corporates seeking to create demand down its supply chain. But success or failure of these programmes and initiatives is often down to convincing governments and institutions in the developing world to recognise the benefits and adopt them. That is perhaps where a bunch of global brands working together could have their biggest impact.

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