The rules governing the leasing of farm and ranch property have gone through an enormous transformation over the past 20 years. In the 1970s, the Internal Revenue Service developed a set of guidelines for distinguishing leases from various kinds of purchase arrangements. Those authorities gave way to "safe harbor" leasing in 1981 and "farm finance" leases in 1982. Those provisions have now been repealed or have expired so that the determination of what is a lease is governed by pre-1981 law.