Total scattering experiments using high-energy synchrotron X-rays and spallation neutrons are providing new insights into the structures of nanoscale and poorly crystalline materials of environmental and mineralogical relevance. The pair distribution function (PDF) derived from these total scattering data is a real-space depiction of the atomic arrangements over short (<3–5 Å), intermediate (up to ~20 Å), and even longer length scales. Structural information can be extracted both directly from the PDF and through modelling. PDF analysis approaches are described using selected examples of natural and synthetic nanoparticles as well as a sample that is a mixture of amorphous and crystalline structural phases. Several applications include combined analysis of the real- and reciprocal-space forms of the scattering data. Greater application of the total scattering and PDF methods to environmental minerals that are nanoscale and poorly crystallized will provide new insight to structure, including structural disorder at different length scales, and help to develop further structure-property relationships.