Sleep training is the process of teaching a baby or child to fall asleep and stay asleep independently. This is done by introducing a consistent bedtime routine and gradually reducing parental involvement in the sleep process. Sleep training can take various forms, including the cry-it-out method, the gradual method, and the no-tears method. While controversial, many parents find that sleep training helps their child get the rest they need and improve their overall behavior and mood. It's important to note that sleep training is not a one-size-fits-all solution and should be tailored to each child's unique needs and temperament.