What is the most effective means of customer acquisition?

45% Direct Mail 27% Exhibitions 23% Websites 22% Telemarketing 17% Email 15% TV/Radio ads 13% Print ads 3% Banner ads 23% Other

This - added to the end of the dot.com boom - has led to a dramatic slump in revenues and put a question mark over the future of many well-known online ventures.

UK internet advertising revenue showed its first ever quarterly decline in the third quarter of last year, when it fell 6.5%, according to the latest available figures from industry body The Internet Advertising Bureau (IAB).

Banner ads have also been hit by the growing availability of ad-blocking software such as Adsubtract and Adwiper.

Unfair advantage

More than 400 marketing managers took part in the Marketing Week survey, in the financial services, government, IT, manufacturing, retail, telecommunications, utilities and service sector.

The target audience for 39% of respondents was adult consumers, 6% wanted to communicate with children and the remainder were concerned with business to business marketing.

Its findings follow a report by US consultants Booz, Allen & Hamilton, which urged internet portals to seek alternative revenue streams, such as subscription and paid content.

Some analysts have argued that measuring the effectiveness of banner ads by click rates puts them at an unfair advantage to print and poster advertising, which have no accurate way of measuring numbers of viewers.

Fighting back

However, internet advertisers are poised to fight back with a new generation of bigger, more intrusive ads.

Earlier this month, the IAB agreed voluntary guidelines to increase the size and prominence of banner ads to make them harder to ignore.

One format, the 'skyscraper' will form a vertical strip down the side of the page and will be much bigger than existing banners.

Another format is a square shape which appears in the middle of page, measuring 336 x 280 pixels, compared to the banner's 468 x 60.