Whether from their own devices or company computers, most employees use social media at work — with or without permission. This could mean trouble and be very expensive for a company that does not take the right steps. Does your company have a social media policy in place? Is it well thought-out? Is it enforced? It better be. Social media usage by employees is full of traps and risks, and employers must recognize the dangers and take steps to mitigate them with well-conceived policies and other protections. Companies that fail to take such measures could face fines, prolonged and expensive litigation and loss of reputation.

Following are seven deadly social media sins that could land your company in scalding water.

1. Ignoring reality: People in your employ are using social media. Pretending otherwise will not be an excuse if problems occur.

2. No policy: Without rules, employees do not know what’s permitted. Do not convey the message to employees that they can do what they want on the Internet or on social media in the office or on work time. This “wild west” approach is very dangerous.

3. Failing to observe and enforce: If you have a policy but are not enforcing it or monitoring what people are doing, you are inviting problems.

4. Lack of understanding: Ignorance of the law is no excuse. There are many laws at play in this arena — slander, libel, trademark issues, copyright, privacy, FTC regulations, defamation and more — and you must learn about them. It can be helpful to consult a professional so you learn and understand the law, and then train and educate your employees. Then you should require employees to acknowledge they understand the training, the rules and the consequences.

5. Leaving open the vault door: Companies collect and store a lot of sensitive information from employees – Social Security numbers, personal information, credit card numbers and other data — as well as from customers. You must safeguard this information.

6. Failure to consider ownership of the information: Who owns the content posted online by your employees — the tweets, blog posts and Facebook posts about products and services? What if one of your employees builds a list of thousands of Twitter followers, then switches jobs and tries to take them? Those followers might be extremely valuable as potential customers.

7. Doing nothing: This is the mortal sin. You must create policies, enforce them, review and update them periodically, keep up with changes in the law, monitor your employees’ usage, train them and make sure they understand who they can go to if they have questions.

Is all this easy or simple? No. But it is the new reality. Fortunately there are professional resources that can help you navigate the process.

Mark Stein, a partner with the law firm Higer Lichter & Givner, practices cyber law, social media law and intellectual property law.