Why toddlers run away
No sooner do you lift your toddler out of the car, set him down on the sidewalk, and turn to wrestle his stroller out of the trunk than he suddenly darts away. When you finally catch up with him it's clear that he doesn't want to ride in the stroller today — he wants to walk on his own.
That's the desire at the heart of this problem. He's not running away to be bad on purpose or to defy you. He simply has a new sense of independence combined with legs that can run. "Toddlers love the feeling of being free and running around," says Patricia Shimm, director of the Barnard College Center for Toddler Development in New York and co-author of Parenting Your Toddler. "You can encourage it as long as you can control where they run."
What you can do about it
No amount of teaching will ensure that your toddler is always as cautious as he should be, so it's vital that you take responsibility yourself for keeping him safe. That means being hyper-vigilant about always creating an environment that's safe for your child.