Most letterbox stickers simply read 'No Junk Mail'. For years I refused to sell stickers with that text on this website. The text is rather vague and subjective; what you see as 'junk mail' may be useful information to me. Should political leaflets be classified as 'junk mail', for instance? Or, what are deliverers of free local newspaper supposed to do when they come across a sticker saying 'No Junk Mail'?

Although I still feel that stickers with the text 'No Commercial Leaflets' are better I've decided to give in to the demand for 'No Junk Mail' stickers. I reckon they're good enough, provided that we can get some sort of definition of 'junk mail'.

There's no definition

In countries that have a sticker scheme for unaddressed junk mail - that is just about the whole western hemisphere apart from Britain - a definition of junk mail is usually agreed by the industry and consumer groups. As the junk mail industry in our country doesn't support a sticker scheme (and even refuses to discuss the idea with consumer groups) we don't have a definition. Until the happy day comes that they industry is able to acknowledge the errors of its way we'll have to muddle along.

My suggestion is to define 'junk mail' as unaddressed, unsolicited and commercial advertisements. In other words, a 'No Junk Mail' sign should stop commercial items such as take-away menus and calling cards from local businesses, but not non-commercial items such political leaflets, local authority magazines and free newspapers.

So what if you don't want to receive free newspapers and/or political leaflets? To stop the first you can get a sign that reads 'No Junk Mail and Free Newspapers' and/or contact the publisher of the paper you want to cancel. Political leaflets are more complicated. If you don't want to receive political leaflets your best option is to ask the political parties you don't want to hear from to skip your letterbox. If the party is a member of the Direct Marketing Association (and the three main parties all are) they have to respect such a request (under article 13.23 of the Direct Marketing Association's Code of Practice). For more information about stopping political leaflets, see 'How to stop political leaflets' on my blog.

Generally speaking, leaflet deliverers are quite willing to respect 'No Junk Mail' signs. True, there are deliverers who simply don't care (in my own experience take-away restaurants are the worst offenders) but most deliverers understand that ignoring a polite request not to receive leaflets is rude and reflects poorly on the company they represent and the industry as a whole.

They're not all 'baddies'. In fact, deliverers are sometimes rightly frustrated with householders for making it difficult for them to do a decent job. If you are going to put up a 'No Junk Mail' sign, consider if deliverers will be able to easily spot and understand the sign. In particular:

• Put the sign on your letterbox, or at least as close to the letterbox as possible. That way the deliverer can't fail to notice it.
• If you live up a long drive (or up steps or behind a gate) put an extra sign up at the end of the drive. The deliverer will be grateful.
• If you are going to make a sign yourself, keep it simple. Deliverers are unlikely to read through a long list with items you don't want to receive and then decide whether or not they got what's listed.

In short, be nice to deliverers and help them to help you.

If your 'No Junk Mail' sign is ignored there's a good chance the culprit is Royal Mail. The company instructs postmen to ignore any type of 'No Junk Mail' sign and wants people to register with its Door-to-Door Opt-Out instead. If the junk mail was delivered by the postman indeed you should either sign up to the opt-out scheme or, if you are already registered, remind Royal Mail not to deliver unaddressed mail to your address. More information about the opt-out scheme can be found on the Door-to-Door Opt-Out page in this guide.

Your options are limited if the junk mail wasn't delivered by the postman. Unfortunately, any 'No Junk Mail' sign is merely a polite request not to receive (commercial) leaflets. The Data Protection Act 1998 gives you the right not to receive addressed junk mail (see 'Contact senders') but there's no such equivalent for unaddressed junk mail. The self-regulatory framework set up by the Direct Marketing Association also doesn't offer help when it comes to enforcing 'No Junk Mail' signs - the industry feels its two opt-out schemes for unaddressed mail are more than adequate (even though signing up to both schemes can no more than halve the amount of unaddressed junk mail you get). You could try contacting the sender directly. Usually you'll get an apology, and hopefully the sender will be more considerate next time.

And what if the sender ignores anything you say? You may want to consider taking more radical action. I can recommend the justice for the price of an envelope approach. Stick the unwanted leaflet in an envelope with a polite note asking the sender to respect 'No Junk Mail' signs in future. Don't put a stamp on the envelope, just hurry to your nearest pillar box and get Royal Mail to notify the sender that an item is ready for collection and that a charge for postage and an admin fee are due.

The reason we don't have a proper sticker scheme in the UK is that the (self-regulating) junk mail industry doesn't like the idea of people putting 'No Junk Mail' signs on their doors. Interestingly, in a discussion about sticker schemes I had a couple of years ago the Direct Marketing Association's head of postal affairs did acknowledge that such schemes are a huge success abroad. However, he felt that introducing a sticker scheme in Britain would be too difficult because we're unfamiliar with such schemes. That there are more people with a 'No Junk Mail' notice on their door than there a people registered with opt-out schemes for unaddressed junk mail is merely an inconvenient detail.

I'd rephrase the Direct Marketing Association's argument as follows:

"A sticker scheme wouldn't work in the UK because Britons are too thick to fully understand the consequences of not receiving unaddressed unsolicited mail. Consequently, Britons need to go through a registration process in which it's explained to them that not receiving unsolicited leaflets may result in missing all sorts of special offers and important information.

As things stand, though, the industry is allowed to regulate itself. That its two opt-out schemes for unaddressed junk mail cover only a portion of all unaddressed junk mail, and that hardly anyone is registered with the schemes anyway, is irrelevant. Until, maybe, politicians start realising that billions of pieces of junk mail could be prevented by making it easier for people to say 'no junk mail'.

• Buy a letterbox sticker