Does it matter who the medical services are for?  What if Dr. #1 pays another incorporated doctor (Dr #2) to do his after hours hospital visits.  For Dr. #1, is Dr. #2 providing medical services?  Interesting because Dr. #1 is providing medical services to a patient by sending Dr. #2.  Dr. #2 isn't providing "medical services" to Dr. #1.  So is Dr. #2 just an independent contractor for Dr.#1 and therefore does not get a 1099 because Dr. #2 is incorporated?  So if not "medical", there would be not reason to send a 1099 to an incorporated dr.....?  (Simple answer is send anyway)