Rights to light are valuable: they give landowners certainty that natural light will continue to be enjoyed by a property - increasing its utility, value and amenity. The right may enable landowners to prevent construction that would interfere with their rights or, in some circumstances, to have a building demolished. Where a development has taken place, but a court does not order its demolition, the court may award substantial damages. It may not be clear which remedy the court will order and landowners may succeed in preventing development even if they raise the issue after building has commenced. Rights to light will usually (and much more commonly than most easements) arise by long use (prescription) rather than any express agreement between landowners, and in many cases those burdened by and benefiting from rights to light will be unaware of their existence. The planning system does not take account of private rights of this sort, and so rights to light can impact on development even where planning permission has been granted.The Law Commission’s recent work on easements, covenants and profits a prendre reviewed the general law and did not examine specific easements. It did, however, highlight the need for further work on rights to light.