Some embodiments include dielectric structures. The structures include first and second portions that are directly against one another. The first portion may contain a homogeneous mixture of a first phase and a second phase. The first phase may have a dielectric constant of greater than or equal to 25, and the second phase may have a dielectric constant of less than or equal to 20. The second portion may be entirely a single composition having a dielectric constant of greater than or equal to 25. Some embodiments include electrical components, such as capacitors and transistors, containing dielectric structures of the type described above. Some embodiments include methods of forming dielectric structures, and some embodiments include methods of forming electrical components.