I have read through the comments and no one touched your question about "Third party administrator". I don't see how that process would benefit a single payer plan. If you read the laws that protect the "business relationship" between the employer and the Third party administrator - you wouldn't want one handling your private healthcare information. The HIPAA laws apply differently to TPA's. They cater to their customer - the business so they can discuss YOU and your health condition. Medical necessity recommends certain treatment courses at varying degrees. Let's say for example that your employer likes Tom Smith better than Deb Doe. The TPA can contact the employer and the employer would dictate to deny and extension of let's say -- Physical Therapy for Tom Smith, he received the amount that meets medical necessity but the Physical Therapist and physician recommend that Tom Smith has additional therapy treatments. But the employer doesn't like him that much so they tell the TPA to deny further PT treatments. Now the same situation is presented for Deb Doe, she has completed her physical therapy treatments and the PT and MD are requesting additional treatments for her -- the employer really likes her so they are fine with Deb Doe getting the additional therapy. You don't have the 1) Health privacy that you think you have with a Third Party Administrator and it is legal. 2) Equality in treatments and intervention is also - to a degree - up to your employer and YOU won't even know it. Even though it is legal - the TPA is going to protect their customer - your employer - so no one is going to tell you that what the TPA has done to Tom Smith and Deb Doe, etc. etc.