Mail preference is forcing charities to re-assess the way they target donors.
Returning from a two-week holiday to discover that you can hardly get through your front door because of all the junk mail is a scenario familiar to most of us - unless, of course, you have signed up to the Mail Preference Service offered by the Direct Marketing Association or the REad Group's itsmypost.com.
The take-up of the MPS illustrates that there is a considerable demand for it. In October 2001, 766,912 people had registered with the MPS. By October this year, that figure had increased to more than three million - an increase of 300 per cent in five years.
However, these services haven't exactly been welcomed with open arms in the sector. The itsmypost website in particular has ruffled a few feathers by generating extra administrative work for charities (Third Sector, 1 and 8 November).
But it's not just the inconvenience. Many charities have been reliant on direct mail as a means of communicating with warm and cold donors for more than 20 years, and the MPS has had a significant effect on returns, according to Sonya Burke, direct marketing manager at Amnesty International.
"We have reduced our volume of direct mail because it's not as profitable as other methods," she says. "But I don't think it's just because of the MPS - list prices are higher now, too. People are also a lot more wary of giving their contact details away.
"We will be looking at how effective our direct mail is over the next year and are considering whether we should use it at all."
Given that the DMA is also considering introducing an MPS service for door drops, when the mail is not addressed to anyone, such a course of action would certainly seem prudent. And Amnesty International isn't the only charity looking at other options.
Libby Scott, a direct mail officer at Unicef, says: "We are in the process of conducting research into people's preferred methods of communicating.
"Increasing numbers of people are donating online, and those that do definitely prefer to be contacted by email. We are looking at expanding our use of email because it's free, but we have only a limited number of addresses on our database. The requirements are stricter too - people have to opt in instead of opting out."
Marc Middleton Heath, managing director of PR and marketing company Catalyst Works, also believes the future lies in electronic mail."It can help reach new markets and the costs are much lower," he says. "There are also new profiling techniques that make it easier to target people.
"It may be true that people have to opt in, but the harder you have to try to get people to opt in, the better the returns are, because the contacts are more likely to offer lifetime value."
To some, however, the advent of mail preference services does not necessarily sound the death knell for direct mail and may even be a good thing for charities.
David Burrows, head of fundraising at TDA, says: "It's becoming harder to use direct mail, but it's becoming harder to use most forms of media because it's such a crowded market.
"I don't think there is a particular crisis in direct mail, and I think services such as itsmypost are a healthy thing because it means charities are not sending mail to those who don't want it."
Peter Foy, donor development manager at the Church Urban Fund, agrees. "The MPS has taken out the 'unknowns' from mailing lists, so now you have a better idea of whether people will open the envelope, "he says.
"The MPS has made us work smarter and think more about the appearance and content of our mail. The market is better educated now - you can't just use a picture of an African baby crying and hope that's enough. You have to stand out from the crowd and remember that people want to know what's in it for them."
Middleton Heath, however, claims the sector has failed to rise to the challenge posed by the MPS. "There's a lot of organisations sending out similar stuff, and the market will reach saturation point very quickly,"he says.
A spate of negative publicity about junk mail and the Daily Mail's campaign in August and September to encourage readers to 'de-junk' their lives led to an increase in the number of people signing up to the MPS.
In August, 2,994,491 people were registered with the service. By the end of October this had risen to 3,170,044 - an increase, but perhaps not as significant as the Mail would like.
Robert Keitch, director of media development at the DMA, says: "The MPS is a very blunt axe. When people realise that it means not receiving any direct mail at all, they may think twice.
"Charities wouldn't use direct mail if it wasn't effective, but there are some who are better at it than others."