If you had to tick a box to choose the most influential voice in the brewing industry today would you choose the British Beer and Pub Association, the Independent Family Brewers of Britain – or Siba, the Society of Independent Brewers?

To use a popular phrase of the moment, it's a no-brainer. To extend the cliche, Siba is the elephant in the room. It sets the pace. Powerful people in government and even the giant pubcos sit up and listen when Siba comes calling.

I came away from the organisation's annual conference in York last week reeling at the size and the effectiveness of the organisation. It has around 450 members. They are dedicated and passionate people, with a deep-seated belief in brewing quality beer, most of it in cask-conditioned form.

As well as attracting some top drawer speakers, there were companies falling over themselves to sponsor the conference, the annual brewing awards and many other aspects of Siba's activities.

Maltsters, hop merchants, bottle and cask makers, and manufacturers of brewing equipment had stands all round the conference hall. They recognise that Siba is a powerful force and, against all the odds, is recording increased sales for its beers at a time when bigger brewers are in free fall.

The organisation has come a long way from 1980 when a handful of micro-brewers, spearheaded by Carola Brown at Ballards in Hampshire, launched the Small Independent Brewers Association, as it was first known. With the exception of Camra (the Campaign for Real Ale), who recognised a kindred spirit, not many people took Siba seriously.

The regional brewers in particular were either patronising or downright rude. There were mutterings about “beer in a bucket merchants” and poor quality. The main attitude was simple: ignore Siba and it will pack its tiny tent and disappear.

But the tent has turned into large marquee. The number of regional brewers has more than halved. Many of them didn't have the bottle to take on the national brewers and gave up the ghost.

Siba doesn't lack bottle – even though most of its product comes in cask form. Today it's a large, impressive and remarkably professional body. And it has two key successes that have helped transform not just the brewing industry but have also impacted on consumers as a result of increased choice in pubs.

The first success – and it was a Siba hobby horse from its inception – was Progressive Beer Duty (PBD). The demand was simple: smaller brewers were at a disadvantage as they paid the same levels of excise duty as even the giant national producers who enjoyed “economies of scale” thanks to sophisticated and computer-controlled equipment.

After years of lobbying, PBD was introduced in 2002. At first he benefits went only to brewers who produced not more than 18,000 barrels a year. That was increased a couple of years later to 30,000 barrels.

The results have been spectacular. Many new brewers have entered the industry while existing craft brewers have been able to invest in new equipment and even buy pubs as showcases for their products.

The second success has been Siba's Direct Delivery Scheme (DDS). This was the brainchild of Nick Stafford of Hambleton Ales in North Yorkshire. The scheme was the result of craft brewers finding it impossible to get their beers into pubco outlets.

They were told that, on top of discounts, they would have to drive long distances to depots to drop beer off, then return to pick up the empties. There was no profit to be made,

DDS allows the brewers to deal direct with individual pubs. It has been such a success, with giant pubco Enterprise Inns part of the scheme, that it is now a subsidiary company within Siba, with a database of pubs throughout the country.

The winners have been not only Siba members but also publicans and drinkers. There is now greater choice in pubs. Drinkers are no longer confronted by national brands but can choose from a wide variety of beer styles.

Siba is a great British success story. It's good to know, in the age of global giants, that occasionally the small guys can win.