Europe's troubled newspaper industry is keeping a close eye on the outcome of experiments by English language sites to charge for content but is reluctant to install paywalls for fear of losing readers.
The New York Times, The Times of London and the Financial Times have all introduced paid subscriptions for online content in recent months but so far continental dailies have been slow to follow suit.
While largely agreed that the industry's future is online, delegates at the ongoing European Newspaper Congress in Vienna are trying to work out not only whether clients would be prepared to pay for content but also how much.
"A paywall like in The Times of London where everything is subject to payment, we definitely won't do but we are taking a look at the New York Times," said Peter Hogenkamp, head of digital media with Switzerland's NZZ group.
Since March, NYT readers can access up to 20 articles per month for free, but above that, they have to pay -- a similar system to that of the Financial Times.
The Times of London however has gone farther and is "available exclusively by subscription", as it states on its website, even if the first month only costs one pound (1.12 euro, $1.67).
Publishers of the New York Times say the paper has signed up more than 100,000 paid subscribers for NYTimes.com since it began charging for full access to the newspaper's website at the start of last month.
The Times of London said that around 105,000 people paid to read its content in the first five months after it threw up a paywall last July.
With newspaper revenues shrinking across the continent, some paid Internet content is unavoidable, media professionals admit.
"If attention turns increasingly to the Internet, we must rethink the dividing line between paper editions that require payment and free online content," said Hogenkamp.
But a big fear is the loss of readership.
"We don't want to lose readers by being the first to introduce a paid service," said Steiro Gard, editor-in-chief of Norway's Bergen Tildende.
"It's easy to lose ground, the offer has to be really good," added Joachim Tuerk of Germany's Rhein-Zeitung, which is still holding off on introducing paid content.
Delegates at the conference, which coincides with Tuesday's UN World Press Freedom Day, said that newspapers need to establish how much readers are willing to pay and develop easy-to-use payment systems.
Creativity is also a must to sell paid content to Internet users spoiled with free content for the past 15 years.
"We have to try things, even if we make mistakes. But with new products, because we are not going to sell something that was previously free," said Hogenkamp.
In Portugal, Madeira's Diario de Noticias took the big step and introduced paid subscriptions for all online content in February to compensate for falling ad sales: and traffic on its website has remained stable, helped by readers outside the island.
"Online subscriptions now make up 10 percent of newspaper subscriptions," said director Ricardo Miguel Oliveira.
The solution may be in mobile phones and tablet computers.
"People are used to paying for mobile services," noted a delegate from Germany's Axel Springer group.
"We must see how far paid services can be extended to access from a desktop computer or laptop."
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