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This Act attempted to clarify the circumstances in which various kinds of Easement or Profit aprendre could arise by prescripton; but, in practice, the Act runs alongside common law prescription and the doctrine of LostModernGrant.

For an easement to arise under the Act, it must have been in continuous use for 20 years; for a profit the relevant time is 30 years. After this time the easement is recognized, but capable of challenge. After 30 40 years for easements or 60 for profits, the right can no longer be challenged: it is absolute.

The Act does not override the ordinary requirements for the existence of an easement or profit. The right claimed must 'lie in grant', and exist for the benefit of the dominant tenement against the ServientTenement, and so on. There are particular peculiarities in the way the time periods are calculated. For example, the time period runs up to the court hearing, not up to the time the right was asserted. So any time between instituting proceedings and the case being heard is added to the totoal time. However, time is subtracted when the servient owner is deemed to be incapable of resisting the establishment of the right. For example, any time the servient owner (the beneficial owner, in this case) is a child is subtracted, as is any time during which the owner is deemed to be legally incapable as a result of mental illness.