A single word in a trust instrument can mean the difference between an interest that passes to a beneficiary's estate and one that evaporates entirely. This chapter starts with the core distinction between vested and contingent interests, including the difference between vesting in interest and vesting in possession, then examines what happens to each type of interest when the beneficiary dies early. It moves on to conditions precedent and subsequent, interests vested subject to divestment, and the presumption of early vesting that resolves ambiguous wording — illustrated by the contrast between 'to B at 25' and 'to B, payable at 25'. Finally, it traces the three stages an interest may pass through and the hierarchy of gift-overs and resulting trusts that decides where the property goes when a contingency can never be met.
