Matt Simpson, the chairman of the IPA Digital Media Group, said that Google has approached behavioural advertising in a responsible manner, but he warned it could attract criticism.
"Privacy is such a hot topic at the moment, but if Google gets the message out loud and clear, there will be little for consumers to get upset about," he said.
Google launched the new behavioural targeting system on the search engine's AdSense partner sites and on YouTube. The ads will associate categories of interest with a user's browser, based on the types of sites the user visits and the pages viewed, which are tracked via a cookie.
A tool called Ads Preferences Manager will let consumers view, delete or add interest categories to make the ads more relevant.
Users can opt out of the advertising cookie for the AdSense partner network.