It isn't enough to drive sober, as this NTF Vast campaign points out, because distracted driving of any kind can slow your reaction time and cause you to miss crucial changes in driving conditions up ahead.
The Swedish road safety organization had these three prints made by the Cordovan Communication advertising agency to target texting specifically as a dangerous activity while operating a vehicle. While you're typing an SMS to a friend much of your attention is inevitably on the screen of your iPhone, making a collision all the more likely.
According to the NTF Vast campaign, sending and receiving text messages while driving reduces your awareness of the street to a point that's equivalent to having a blood alcohol level of 0.15%. A wine bottle shaped callout and a few sloppy typos demonstrate the point.