Emphasis of matter is a type of paragraph in, or section of, an auditors' report on financial statements. Such a paragraph is added to indicate a significant uncertainty or other matter, which is disclosed appropriately in the notes forming part of the financial statements, but which the auditor considers is significant or important enough to warrant a mention in their report.
An emphasis of matter paragraph does not qualify the auditors' opinion; in fact, such paragraphs typically begin by stating Without qualifying our report....
Under the framework of the International Standards on Auditing (ISA), the emphasis of matter paragraph / section is placed after the opinion paragraph (and, consequently, towards the end of the report), in the auditor's report.