A prescriptive easement—also known as an easement by prescription or an adverse easement—is an easement (right to use property) created by a use of property (the servient estate) that is open, continuous, and adverse to the owner of the property (the servient estate).

To satisfy the requirement that the use be continuous, the use must take place over a required period of time—which may be specified in a state’s court opinions (common law or case law) or in its statutes if the state legislature has written the law regarding easements into statutes or code. If the state legislature has written a law in statutes or codes the law is said to be codified.

In Maryland, a prescriptive easement is established when an individual uses another's property openly, continuously, and adversely without the owner's permission for a statutory period. The use must be such that it could give the owner a reasonable notice of the claim. Maryland law requires a period of 20 years for the establishment of a prescriptive easement. This period is codified in the state's statutes, specifically under the Maryland Courts and Judicial Proceedings Section 5-103. It is important for the use to be uninterrupted and without the consent of the property owner during this time. If these conditions are met, the user may be able to claim a prescriptive easement, granting them the right to continue using the property in the manner they have been. It is advisable for individuals seeking to establish or contest a prescriptive easement to consult with an attorney who is knowledgeable in Maryland property law.