Last year, residents' parking permits (RPP) were introduced to our area of Kemp Town.

The point of such a scheme is to ensure the availability of parking spaces for residents.

However, in the past few weeks, partly because of the crackdown on double yellow parking violations, the availability of residents' spaces here has decreased markedly.

I have discussed the matter with local traffic wardens, who recognise the problem but simply lack the resources to cope.

On a typical weekday evening, about one-third of local residents' space is occupied by cars without permits.

The figure at weekends is far higher. Residents with a valid permit but unable to find a space quite rightly wonder why they should belong to a scheme yielding so little benefit.

Evidence from other parts of Britain (or indeed in most of Europe) suggests RPP schemes are most successful when accompanied by pay-and-display meters.

Non-resident visitors can then park legally by paying for their desired time and will be less tempted to overstay their welcome.

Traffic wardens need only check for display tickets rather than laboriously jot down number plates and times. The cost of installing the meters is recovered from the fees collected.

Pay-and-display meters are a proven, cost-efficient complement to residents' parking permits.

One does hope Brighton and Hove City Council will look into this matter before further extending what is currently a poorly-designed and inefficient scheme for rationing scarce parking space.

-Professor George Irvin, Sussex Square, Brighton