The structural and social environment, as well as opportunities for cognitive and physical activity, are important for all species of animals. An appropriate environment includes shelter and a comfortable resting area, in which animals are free from fear and distress and have the ability to express normal, species typical behaviors. Lack of control over one’s environment is one of the most profound stressors for animals. The stress induced by even short-term confinement in an animal shelter can compromise health; and when confined long-term, animals frequently suffer due to chronic anxiety, social isolation, inadequate mental stimulation and lack of physical exercise. Proper behavioral healthcare is essential to reduce stress and suffering as well as to detect problem behaviors that may pose a safety risk to humans or other animals.