The way that your ski boot fits, supports, and holds your foot and ankle is vitally important to the foundation of your ski experience. Essentially your boots transfer energy from your feet, to your bindings, and subsequently to your skis. If your ski boots do not fit properly you're asking for a world of trouble. Select boots that are sized too large and you will end up working certain leg muscles more than necessary, resulting in cramps and increased fatigue. Select boots that are sized too small and your feet will hurt badly…very badly. To avoid all of these potential issues it is crucial that you take the steps necessary to get the right ski boots from the start. One of the best ways to tell if a kids ski boot is fit properly is to have the child kick their toes forward and use a pen or pencil to see how much room is behind the heel. An accurate fit for kids ski boots would be one pen or pencils width behind the heel; this gives a snug fit with a bit of room for growth.