Zoning laws govern what can and can't be done with land. Essentially, zoning laws are the reason you don't have a Walmart in your back yard or a sewage processing plant right next to a town square. Zoning is a bit more complex than that, of course: It's the division of land into subdivisions that will have varying restrictions of what can be built on each piece of property [source: Curry]. Make sure you'd even be allowed to build a house on a vacant lot before buying and trying to start construction.
Figuring out the basics of zoning shouldn't be too difficult. For instance, certain areas will clearly be zoned for residential building. You can seek out the zoning office in any U.S. county or look it up online to find useful records for any parcel of land. While you're digging around in those records, make sure to pay attention to the county's long-term land use plans and scheduled road additions. Those will dictate future construction and could spell the difference between a nice quiet front yard and a house uncomfortably close to an interstate 10 years from now [source: Curry].
Even after successfully navigating zoning restrictions, you should still be aware of a few limitations that impact what you can and can't build on a piece of property. Next up: the power of homeowner's associations and city ordinances.