Dogs, cats and even birds have all been specially trained as therapy animals.
Now, researchers in central Florida are among the first in the country to establish a formal center to study the benefits of horse therapy on soldiers with PTSD.
Michelle Dunaway shows us how time with gentle giants may have a big impact.
A significant number of the 70 soldiers in the research study reported improvements in depression symptoms.
They also improved interpersonal relationships following the ten-week horse therapy sessions, with help from medication and other therapies.