Explain the duty of care of professionals.

The professional's standard (the unit's foundation): the professional owes the care of the reasonably competent practitioner of the profession — not the ordinary person's standard (Unit 3.1.3's reasonable person), but the SPECIALIST'S: the skill-and-knowledge the profession's ordinary member possesses, exercised with the reasonable diligence. The duty's faces: The competence's scope: the professional practises within the competence — the specialist's higher standard in the specialty; the generalist's honest limits (the referral's duty where the case exceeds); The updating's duty: the current knowledge-and-practice (the outdated method's risk); The information-and-advice's duty: the client's/patient's INFORMED decisions — the professional's full-and-fair explanation (the informed-consent face — the medical world's classic); The diligence's duty: the matter's careful pursuit (the deadlines, the records, the follow-up); The loyalty's overlay: the conflicts' avoidance, the confidentiality (the professional-ethics layer — the councils' codes); The standard's proof: the expert's evidence (the malpractice trial's own expert-dependence — the profession judging itself, the honest critique).