Critical illness has lasting consequences on the mind and the body. Acute sequelae include a decline in cognitive function known as delirium. Increased interest in improving outcomes for intensive care unit survivors without a high incidence of delirium has initiated a focus on an array of nonpharmacologic interventions in many countries. One such intervention is animalassisted intervention. As the role of animals in human healing is being recognized by clinicians, need is increasing for formal and professionally directed therapies. This review ascertains the effect of interaction with animals on critically ill patients. Emerging evidence indicates that animal-assisted intervention improves the efficacy of critical care regarding primary symptoms and secondary factors of delirium.