Supply constraints are broadly defined as limitations of the ability of a market to deliver new stock. These constraints generally fall into three categories, with some overlap among them: • Legal/institutional: Zoning and land-use regulations limit the location, quantity and/or pace of new development. • Geographical/physical: Physical limitations such as waterways, physical features and soil conditions limit the amount of new development. This category may also include the effect of existing development at a scale and density that limits available sites, resulting in a “crowding-out” effect. Political/cultural: Local opposition to development is not codified through regulations, but which nonetheless is palpable and limits supply.