The fiduciary field is a specialized function not directly related to ordinary commercial banking operations. Commercial bank trust departments, nevertheless, are by far the most important group of corporate fiduciaries. Trust business is generally handled by a specialized and separate staff (except in the smaller banks), and the operations of the trust department are subject to a separate body of law and traditon.
For some small banks, however, the operation of a trust department is not profitable by itself; these banks run their trust departments primarily in order to be able to offer a complete package of banking services.