Applications of X-ray spectroscopy to air, water, and soil pollution studies are covered in detail in this essential publication. Air pollution can hardly be studied by any other method to such an extent. Much of our present knowledge in this field was obtained by laboratories using many of the same methods described in this work. A number of examples illustrate the contribution of X-ray emission spectroscopy and its capabilities in the area of water pollution. Examples of soil pollution studies by the use of biological monitors is also presented.