The hand is the most common site for bite injuries. Because of specific characteristics of hand anatomy, bite mechanics, and organisms found in human and animal saliva, even small wounds can lead to aggressive infections. Failure to recognize and treat hand bites can result in significant morbidity. Human and animal bites most commonly lead to polymicrobial bacterial infections with a mixture of aerobic and anaerobic organisms. Pasteurella species are commonly found in dog and cat bite wounds, and Eikenella is characteristic of human wounds. Staphylococcus, Streptococcus, and anaerobic bacterial species are common to all mammals. Although public health measures in developed countries have been highly effective at reducing rabies transmission, dog bites remain the most common source of rabies infection worldwide. Human bites can transmit HIV, hepatitis B, or hepatitis C, especially when contaminated blood is exposed to an open wound. Appropriate management of any mammal bite requires recognition, early wound cleansing, evaluation of injured structures, and infection prophylaxis. Structural repair is performed as indicated by the severity and contamination of the injury, and wounds may require delayed closure. Wound infections typically require débridement, empiric antibiotics, and delayed repair or reconstruction.