What the word reasonable is doing in a contract

The vaguest word in the document is there on purpose

Reading a carefully drafted agreement and arriving at a phrase like reasonable endeavours, reasonable notice or a reasonable time produces a distinct sense that somebody gave up. The rest of the page defines everything to the day and the decimal place, and then a word arrives that appears to define nothing.

It is doing the opposite of giving up. A precise number is a commitment to a single answer for every future situation, including situations nobody has imagined yet. Reasonable is a deliberate substitution of a standard for a rule, and drafters reach for it exactly where the alternative is a number that will be wrong in some foreseeable cases.

Rules and standards fail in opposite directions

A rule is easy to apply and blunt. Fourteen days is fourteen days, which makes it wonderfully cheap to administer and produces absurd outcomes at the edges, since a case where two days would obviously suffice and a case where two months would barely do are treated identically.

A standard is expensive to apply and flexible. It asks what would be appropriate in the circumstances, which means the circumstances have to be examined every time and the answer cannot be known in advance. Most agreements use both, and the allocation is informative: rules where certainty matters most, usually money and dates, and standards where the situations vary too much to be enumerated.

It is measured against circumstances, not against opinion

The common assumption is that reasonable means whatever the parties think is fair, and that is not how the word functions. It is assessed objectively against context — what is normal in the trade, what the parties knew, what was practical, what similar situations have produced. Personal conviction that something is unreasonable is not the test.

This is what makes the word usable in practice. Two parties disagreeing about a fourteen-day notice period have nothing to discuss, because the number decides. Two parties disagreeing about reasonable notice have a great deal to discuss, and the discussion runs on evidence about what the situation actually required. That is slower and it is far more likely to produce a sensible result at the edges.

The graded family of endeavours

Efforts language comes in strengths, and the differences are real rather than stylistic. Reasonable endeavours generally requires a genuine attempt without demanding sacrifice. All reasonable endeavours sits higher. Best endeavours is the strongest of the family and can require substantial cost and effort in pursuit of the outcome.

How these are interpreted varies by jurisdiction and by the surrounding wording, and there is genuine disagreement about where the boundaries between them lie. What is not disputed is that they form a ladder, and that a party negotiating a document usually knows precisely which rung it is standing on. Anyone reading one should at least notice that a rung has been chosen.

Where the word conceals a disagreement

There is a less flattering use, and it is worth naming. When two parties cannot agree on a number, a standard word is sometimes inserted so that the document can be signed. The disagreement has not been resolved; it has been deferred to a moment when it will be more expensive and more consequential to resolve.

A reader cannot easily tell the two uses apart from the page alone, which is one reason the word attracts suspicion. A useful signal is whether the surrounding clause supplies any texture — factors to be taken into account, examples, an upper or lower bound. Texture suggests the standard was chosen deliberately. A bare word beside otherwise very precise drafting sometimes means the negotiation stopped there.

Reading it without either panic or complacency

The proportionate response is to notice which obligations are governed by standards rather than rules, and to ask whether those are the obligations you actually depend on. A standard attached to something peripheral is unremarkable. A standard attached to the central promise of the arrangement is worth a conversation before signing, since it is precisely there that the absence of a number will be felt.

And if a specific number matters to you, ask for it. Standards are frequently in a document because nobody objected, and substituting a figure for a word is one of the more achievable amendments in ordinary commercial dealing. What reasonable means in any particular agreement is a question for somebody qualified to advise on that agreement; what it is doing there is a question of drafting technique, and the answer is the same everywhere.