Union activists have introduced a record number of employees into workplace training in the past year.
The number of workers signing up for courses has increased from an average of 4,000 a year to 8,000 in the last year, according to the Learning and Skills Council.
Since April last year s given learning reps have had the legal right to time off to help colleagues get onto training courses.
Unison, the largest union, says more than 4,000 of the public-sector workers it represents are enrolled on courses as a direct result of its own army of 1,500 learning reps.
Dave Prentis, Unison's general secretary, said: "This has been a remarkable success story. The union gets new activists involved with a further spin-off in recruiting new members to the union.
"Employers get a better trained workforce and employees get access to training and better prospects as a result."
Since the legislation came into effect, the number of people volunteering to be learning reps has also increased - from 900 a year to 2,000 in the past year.
The scheme has led to 70 learning centres being set up in companies around the country.
The LSC says 80 per cent of the new learners it has recruited did not have GCSE-level qualifications before being approached by learning reps.
A spokeswoman for the Confederation of British Industry said: "The union learning representatives are particularly effective in the area of literacy and numeracy. The scheme is most effective where there is a good relationship between the learning rep and the human resources department of a company."
But with union membership at its highest in the public sector, the CBI says the scheme will have no impact in private companies, which still rely heavily on other government initiatives, such as Investors in People.
Union learning money can be applied for by any trades union, whether or not it is TUC-affiliated, as long as the bid is made in conjunction with the employer.
The Association of Colleges, which has worked closely with Natfhe, the lecturers' union, on the introduction of union learning reps, says the scheme has proved a success.
Maggie Scott, the AoC's curriculum and quality adviser, said: "We worked with the TUC and Natfhe to help learning providers get the best out of their local colleges. Learning reps are well placed to make that connection between learning and employment."
Weetabix, the Northamptonshire-based cereal manufacturer, pre-empted the legislation by arranging with its unions to advertise for learning reps before the law came into force. It says the reps have increased the productivity of shop-floor staff.
New recruits are required to read a manual setting out the factory's procedures. The lack of basic skills meant that many had to have the manual read to them.
Learning reps have been introduced in colleges in the south-east by Natfhe in the first year since the legislation and pound;320,000 has been provided to get them into every college in the country.
Danny Bertossa, of Natfhe, said: "We were the first to introduce this to teachers. We found that people who don't have basic skills problems are sometimes reluctant to admit that they have other training needs. That's what we've been looking at."