Professionals advise their clients. Does this advice constitute professional conduct or speech? Professional advice is speech that is protected under the First Amendment, but at the same time, professional conduct can be regulated by the states, so professional speech can, incidentally, be involved in such regulation. Many lower courts and scholars adopt this view, and thus, professional speech receives less protection than other speech does. However, professional speech should not be treated as having less protection under the First Amendment. The distinctive character of professional speech is its nexus with the knowledge community. Professionals belong to the knowledge community. The knowledge community creates and maintains professional insights, and each profession conveys its insights to its clients. The interests of the professional speech of the knowledge community are combined with the standpoint that the protection of free speech is not only a subjective right but also an objective right. This way of thinking can provide a new perspective on restraining government discretion.