If you’ve got a new car – you probably don’t have a spare...

Newer model cars have a LOT more room in the trunk...  

That’s because they’re skipping the old-school standard spare tire and jack. In their place, you most likely have a cheap air compressor and sealant kit, at best. Those may be fine for minor punctures through the tread. But if the puncture is large or is in the sidewall, help will be needed. You really need to take a few minutes to go over tire issues in your owner’s manual with any family members who will be driving the car.

You can buy "run-flat" tires that allow you to drive on them for a while after they've been punctured. They are not always easy to find as they account for less than 1% of the tire market. Plus, they are more expensive than regular tires.