Final answer:
The principle requiring that professionals remain within their scope of legitimate practice is the principle of nonmaleficence, highlighting the importance of avoiding harm in the medical field.
Step-by-step explanation:
The principle that requires we remain within our scope of legitimate practice is the principle of nonmaleficence. This ethical principle underlines the importance of not causing harm and is one of the core values in the medical and healthcare professions. In clinical settings, it ensures that patients are not subjected to unnecessary harms and that any potential harms are minimized and justified by the benefits of effective treatment. The principle of nonmaleficence is closely related to the principles of beneficence, which requires that actions should be for the good of others, autonomy, respecting a patient's right to make decisions about their own healthcare, and justice, ensuring fair and equitable treatment in healthcare practices and research.