The Cambridge Dictionary defines "reasonableness" as "the fact of being based on or using good judgment and therefore being fair and practical." For litigants in the discovery phase of litigation, being "fair and practical" may have different connotations and can be quite subjective. Can both plaintiffs and defendants—opposing parties in an adversarial system—ascribe the same meaning to "reasonableness" to cooperate in discovery? Is it reasonable to believe that adversarial parties are likely to reach an agreement as to what is "reasonable" in discovery? The Federal Rules of Civil Procedure answer with a resounding "yes."

The Federal Rules have been guiding litigants for decades and include several references to reasonableness. Indeed, for more than four decades, Federal Rules amendments have infused concepts of reasonableness, cooperation, and proportionality into the inherently adversarial process of litigation. The notes of the advisory committee to the 1980 Amendments to Federal Rule 26 were initially skeptical about litigants' ability to agree on discovery planning, observing that "there has been widespread criticism of abuse of discovery," and, in "the judgment of the committee, abuse can best be prevented by intervention by the court as soon as abuse is threatened." Thus, "counsel who has attempted without success to effect with opposing counsel a reasonable program or plan for discovery is entitled to the assistance of the court."