text: in the medical field what is a d.o.?   a doctor of osteopathic medicine  osteopathy is a system of therapy founded in the 19th century based on the concept that the body can formulate its own remedies against diseases when the body is in a normal structural relationship, has a normal environment and enjoys good nutrition.  an md (medical doctor) goes to a school of medicine, and a do (doctor of osteopathy) goes to an osteopathic school of medicine.   for a longer answer:  from ohio state university's school of medicine -  "md or do - is there a difference? a medical doctor (md) and a doctor of osteopathic medicine (do) generally have the same educational background. both are required to complete an undergraduate degree -- usually with an emphasis on science -- followed by four years of medical school, and then a residency program. the length of this residency program varies by the physician's specialty. all physicians must then pass state licensure requirements and examinations.  in regard to primary care, the basic difference between these two types of doctors is narrowing all the time. "the biggest difference is that most dos go into primary care", according to bryan beggin, do, of the osu family practice center at gahanna. the philosophic difference is that the do tends to treat the entire individual, rather than using a disease-specific approach to treatment."