While landowners have a constitutionally protected right to use and enjoy their property as they desire, that right is not without legal, or practical, limits. Many development plans, whether for a large shopping complex or a small garden shed, are thwarted by the limitations of the relevant zoning ordinance, the unique physical characteristics of the property, or both. Most of the time, the landowner must simply revert to a plan that fits within the confines of both law and land.  However, in exceptional circumstances, where strict application of the zoning ordinance to a particular parcel would result in an unnecessary hardship, a variance acts as a "relief valve;" it allows a deviation from the strict terms of a zoning ordinance to permit the owner's reasonable use of the property.