Aggressive panhandling can get you in trouble with the law; aggressive marketing can get you in trouble with your customers. According to a survey released Tuesday by Accenture, "consumers overwhelmingly (76%) cite aggressive marketing as the factor that undermines their trust in business."

The report by the IT services and consulting firm says privacy and trust are key concerns to most consumers, 51% of whom say fear of inadequate protection of their personal data has compelled them to "reject or cancel" doing business with a company.

Glover Ferguson, chief scientist at Accenture, observes in the report that we're entering an age in which networked information systems have profound privacy and trust implications. He says businesses need to take a new approach to privacy that focuses not only on compliance but also on building trust with customers as a means of competitive differentiation.

This may prove trickier than it sounds given another of the survey's findings: 69% of consumers "readily surrender personal information in exchange for rewards such as cash, convenience, and bonus points." At the same time, 97% of respondents expressed concern about privacy, particularly identity theft.

"The survey brings out the paradox but it doesn't explain it," says Ferguson. "This is a basic paradox between convenience and security. It's much more convenient not to lock your house. You get home, you just walk in; you don't have to fiddle around with locks."

A December report from Forrester Research, "The X Internet and Consumer Privacy," also explores this dichotomy. Value and convenience often allay privacy concerns. "We do find that consumers are willing to part with a surprising amount of information," senior analyst Christine Overby says.

For marketers, Accenture's Ferguson sees the establishment and maintenance of trust as critical. "Any private data you have, if you let that get out, you're dead," he says. "It's just so damaging. It's the lecture you give your teenagers about the delicate fabric of trust and how difficult it is to repair once torn. And that's absolutely double or triple-true for business. If you have reputation for letting all your credit-card information leak out, along with people's private data, that's a brand problem that will take a long time to repair."

Glover's recommendation is to focus on the opportunity to strengthen the relationship. "The opportunity is, if you are careful with [customer] information and have any form of trust relationship with a customer, the more you deepen that relationship, the more willing they are to give you more information," he says. "That becomes what I would describe as the incumbent's advantage--the longer and deeper my business relationship, the more information I have, the harder it is for a new entrant to be able to serve a customer at the same level because they don't have that data."