A special field in which exact knowledge is particularly essential as a safeguard against theft is that of the auditor. To many a county treasurer the auditing demands of the government appear to be met when some basis of authority for a payment has been established. Sometimes even then the authority in question is not a legal one for often it may not be established by reference to the letter of the statute but by the precedents set by previous incumbents. Not “What does the law say about it?” but “What did ---- do in such cases?” is apt to be the question uppermost in the mind of the official. How many millions of good money have slipped through county treasurers’ hands through such a procedure will never be known. The state examiner who has not discovered many an old-fashioned county where many such illegal payments have been made is rare indeed. But such post-mortem checking of illegal payments is, for the most part, but a sad business. Modern standards of auditing organization and practice aim to insure more completely that the authority for payment shall be established _before_ payment. The auditor should certainly be wholly independent of the disbursing officer and some authorities would also insist, of the appropriating body. Least of all should the auditing be done by the appropriating body itself or through its committees (as is true in some states) for such an audit through lack of first-hand consideration and definite fixing of responsibility rapidly degenerates into a perfunctory performance. It is even the practice in some counties to audit bills in full board by acclamation! And since so large a portion of county claims are for material and supplies for use in the construction and maintenance of roads, bridges and institutions, the work of audit cannot fail to be closely associated with the purchasing system. The purchasing agent by whatsoever name called, is, after all, a special sort of auditor, dealing with a variety of commodities instead of funds. As in every other branch of public service, successful purchasing depends primarily on exact information, relating in this case, to standards of utility of various articles, the present and the probable future state of the market, the exact condition of present supplies, the honest fulfillment of contracts. Such information may come through stock ledgers, inspectors, trade journals or chemical tests.