I love billboards, and not just because dozens of South of the Border ads have given me and millions of other drivers cheesy entertainment while driving up and down I-95.

Billboards work.

In an era when we’re constantly on the edge of sensory overload, very little unwanted information seeps through. I tune out extraneous stuff on Web pages, rip ads out of magazines, mute TV ads, fast-forward through commercials while streaming video-on-demand, and pay for ad-free premium Spotify.

But I see billboards. Clean Bathrooms Next Exit. Best Morning Drive Station. Outlet Stores 20 Miles. Free Wifi, Heated Pool, Kids under 12 Stay Free.

And Slavery Still Exists.

The U.S. Customs and Border Protection last month launched a human trafficking awareness campaign. I hadn’t seen or heard anything about it–and it’s a topic that I pay attention to. Then I rode by a “Slavery Still Exists” billboard at a busy intersection in Atlanta.

Billboards aren’t right for every business or every ad campaign. But sometimes old-fashioned, low-tech, can be a very effective way to grab people’s attention.