Less than a day is a bit of wishful thinking… perhaps if your child is the absolute right temperament, or a bit older, it might be achievable. Our child was 30 months old. Nonetheless the suggestions and directions in this book work, and they work great. Just take the time to prepare yourself and your child. Children are very driven by reward systems, so make sure to have the entire thing be a positive experience and have some rewards for your kid ready. We took some time to really prepare our kid. We bought a couple books all about using the potty and we bought him big kid underpants. After several weeks of talking about going potty, watching the potty episode of Daniel Tiger, and preparing a sticker chart, getting his favorite treats, and getting a box of 6 construction truck toys, we were ready to launch our first potty training attempt. It was a huge success! Our kid was mostly potty trained on the first day, and definitely potty trained on the 2nd day. We rewarded his successful potty trips with gummy bears cause that’s his favorite treat. He got 1 if he sat on the potty, 2 if he peed, and 5 if he pooped (pooping in the potty took extra encouragement, so we really upped the reward). Please note that when it comes to nighttime potty training, you need to take into account the age of your child. A child younger than about 3 years old has a small bladder and does not have great control over their bladder and usually will not wake up if their bladder is full in the middle of the night. For this reason, keep your child in pull-ups at night. Once they’ve gone a couple months without wetting the pull-ups, then it’s safe to put them to bed in regular underpants. Every child is different, so some may be good when they’re 36 months, others may take longer. To help him reach his goal of not peeing in his pull-ups, we did a sticker chart with a small toy as a reward for every 5 stickers. Every morning he woke up dry he got to put a sticker on his chart. This worked beautifully for us. Our boy went from diapers to just pull-ups at night in 2 days, and then it was another 4 months (he was about 34 months old) when he completely stopped peeing at night. No fuss, no tears, no yelling, no tantrums, just a happy kid wearing big kid underpants playing with a new set of construction truck toys. Just remember, kids will pee the bed once in a while. They will lose control of their bladder once in a while. Do not make the error of yelling or getting upset at them, this can cause then to regress. Let them know it’s ok, it’s not a big deal. Just be prepared for the first 6 months your kid is potty trained with several changes of clothes for just in case. This will help you keep calm if your child has a potty accident. Don’t make a scene, head to the nearest bathroom, clean them up, change them, give them a big hug and move on. You got this!