What is 'eminent domain'?

Eminent domain is the government's constitutional power to take private property for public use, with just compensation paid to the owner. It is one of the four government powers over private real estate (along with police power, taxation, and escheat). Common uses: highway construction, schools, public utilities, urban renewal. The process is called 'condemnation', and the property owner has the right to challenge the taking (whether it serves a true public purpose) and to challenge the valuation of just compensation. The Fifth Amendment to the US Constitution and parallel state constitutional provisions require just compensation; what 'just' means is often litigated. Adverse possession is a way private parties acquire ownership through long, open, hostile use, which is different from eminent domain.