b. provide just compensation.
d. obtain permission of the landowner.
In the United States, Eminent domain is the power of the federal government or the state governments to acquire a private property in order to convert it into public use, while providing just compensation for the landowner, which in turn will give the government permission to possess the land; such compensation is protected in the Fifth Amendment to the Constitution.
Very often, the government uses eminent domain when a person's property is situated in an area where a major infrastructure will be built, like a railway station, for example.