The short answer is yes. It works in the sense that babies can learn to interpret and use signs. As I note below, research suggests that some babies start paying attention to signs by the age of 4 months (Novack et al 2022). By 8-10 months, they start producing signs themselves, and that can be an rewarding experience for families.

Baby sign language teaches babies a collection of easy-to-remember and simple gestures to use as a way of communicating. From about 8 months of age, babies do not have the ability to speak but can start to understand much of what is being said. Babies from this age can easily be taught to use gestures as a way of communicating.

Baby sign language borrows certain words from American Sign Language (ASL) to help parents and babies communicate specific needs such as hunger or sleepiness. Babies are not learning ASL as a full, rich language, but they can use key ASL signs to let you know their immediate needs, wants, and observations.