When you shop Amazon for a product and then see that same product in a Facebook ad days later, it is certainly not a coincidence.

It is a marketing strategy called ad retargeting, and it is dominating online advertising.

Here’s how it works:

• Most consumer-focused websites have long utilized what is called a “cookie” to track your interactions with their site.

• The first time you search for a product, the brand’s website saves a cookie to your browser that can be read or modified by the site leaving it.

• The site then buys ad space on another consumer website.

• When you visit that site, you are served an ad customized for you based on what that cookie collected about your browsing behavior on the prior site.

It is certainly not an exact science; occasionally you will see ads for products you have already purchased. It does work, however.

CMO.com reported in 2013 that ad retargeting can boost digital ad response by 400 percent.

While the whole idea may remind you of “Minority Report,” CMO reports that only 11 percent of the market is uncomfortable with retargeted ads.

The idea is to deliver more meaningful advertising to consumers versus the historic one-size-fits-all approach.

The key to retargeting is to deploy it responsibly by delivering ads that consumers are generally comfortable with.

For example, serving up an ad for books on how to cope with divorce is likely too sensitive a subject for a retargeting campaign regardless of a user’s prior search behavior.

Retargeting can work in both the nonprofit and for-profit world. It is a natural fit for business-to-consumer (B2C) industries, and can also work in some business-to-business (B2B) categories as well.

Given the holiday season that is upon us, as a consumer, you may want to give some thought to how you search for holiday gifts for your significant other.

If you share a computer along with the same user profile, your loved one could be tipped off about your holiday purchase intentions when that PS4 you have been searching for begins popping up as a retargeted ad across multiple websites.

Protecting the surprise is fairly easy. In most browsers, simply select “Tell Sites I Do Not Want to Be Tracked” or “Do Not Track” (from the browser settings) or “Private Browsing” from your browser’s drop down menu.

If the whole idea of retargeting makes you antsy, keep in mind that these brands aren’t likely sharing this data and colluding to sell you.

That kind of information exchange just isn’t necessary in ad retargeting.

Lori Turner-Wilson is an award-winning columnist and managing partner of RedRover Sales & Marketing, www.redrovercompany.com, with offices in Memphis and Nashville. You can follow RedRover on Twitter (@redrovercompany and @loriturner) and Facebook (facebook.com/redrovercompany).