Registered nurses apply the principlism framework (autonomy, beneficence, nonmaleficence, justice) to guide clinical decision-making in complex ethical situations. Moral distress arises when nurses know the ethically correct action but face institutional or systemic barriers to carrying it out, and recognizing this distress is critical for maintaining professional well-being. Informed consent requires verification that the patient understands the proposed treatment, has decision-making capacity, and consents voluntarily without coercion; emergency exceptions apply only when delay would result in serious harm and consent cannot be obtained. RNs hold professional accountability for delegation decisions, documentation integrity, incident reporting, and the obligation to refuse unsafe assignments when patient safety is at risk. Mandatory reporting obligations extend to child abuse, elder abuse, communicable diseases, and impaired colleagues, overriding confidentiality when required by law.