The herein described Adaptive Ergonomic Positioning device (“AEPD”) relates generally to the field of surgery and other medical or healthcare procedures. The AEPD can be adapted for use with most standard surgical tables and surgical chairs where the patient must be positioned prone during a particular procedure. The AEPD may also be used for certain procedures where the patient may be positioned supine. The AEPD support assemblies are highly adjustable and deliver improved ergonomics for both patients and providers. Patients of different morphology can be comfortably positioned in prone with their head and neck in a neutral position, and shoulders in a forward flexed, slightly internally rotated position. The AEPD can be adjusted to accommodate patients with neck and shoulder mobility restrictions, without any effect on provider accessibility to the surgical or treatment site.