The new American Law Institute Medical Malpractice Restatement posits a novel rule in § 6(b) that would authorize the use of medical-practice guidelines as a standard of care for medical-malpractice litigation. However, it would only be a “safe harbor” shield; guidelines could not be similarly used by plaintiffs as a sword. For defendants, the rule would transform what heretofore has been indisputably hearsay evidence into prima facie proof that would serve as a substitute for expert testimony, and which would be sufficient to defeat a malpractice claim. Plaintiffs wishing to use practice guidelines would be relegated to the “learned treatise” exception of the hearsay rule.