Microsoft Corp. and Ask.com called on the technology industry to craft safeguards to better protect consumer privacy, answering a growing chorus of criticism about the amount of data Internet companies collect about their users.

The project, proposed Monday, would bring together businesses, advocacy groups and academics to develop a set of guiding principles that would help alert users when their online behavior is being tracked and for how long that information is retained. The idea is to create a single standard for search engines and online advertising to replace the current hodgepodge of privacy policies.

"This is all about trust," said Peter Cullen, a chief privacy strategist for Microsoft