Brachial plexus birth palsy (BPBP) is defined as an injury to any nerve root of the brachial plexus during difficult delivery. BPBP is relatively rare; its incidence has remained constant over the last few decades, mostly due to unpredictable risk factors, such as shoulder dystocia. Both diagnosis and assessment of spontaneous recovery is based on clinical examination. Electromyography is difficult to interpret in the newborn and is therefore not meaningful. MRI of the cervical spine requires sedation or general anesthesia. Searching for a pre-ganglion tear prior to surgery is indicted. Prognosis depends on the level of the injury (pre- or post-ganglion), size and severity of the post-ganglion tears, speed of recovery, and quality of initial management. Although spontaneous recovery is frequent, some children suffer various degrees of sequelae, up to complete loss of function of the affected upper limb. Recent publications have improved general knowledge and indications for surgery. However, some aspects, such as indication and timing of nerve repair continue to be debated.