In the USA, the external auditor also performs reviews of financial statements and compilation. In review auditors are generally required to tick and tie numbers to general ledger and make inquiries of management. In compilation auditors are required to take a look at financial statement to make sure they are free of obvious misstatements and errors. An external auditor may perform a full-scope financial statement audit, a balance-sheet-only audit, an attestation of internal controls over financial reporting, or other agreed-upon external audit procedures.