The American Crystallographic Association, Inc. is a non-profit, scientific organization of over 2,200 members in more than 60 countries. ACA was founded in 1949 through a merger of the American Society for X-Ray and Electron Diffraction (ASXRED) and the Crystallographic Society of America (CSA). The objective of the ACA is to promote interactions among scientists who study the structure of matter at atomic (or near atomic) resolution. These interactions will advance experimental and computational aspects of crystallography and diffraction. Understanding the nature of the forces that both control and result from the molecular and atomic arrangements in matter will help shed light on chemical interactions in nature and can therefore lead to cures for disease.
Membership in the ACA is open to any person who is actively interested in the purposes of the Association. Student members are very welcome and their contributions to the life and vigor of the Association has always been important.
Meetings are held annually in July, except every third year when they are held in May due to the IUCr Congress. There are 12 Scientific Interest Groups concerned with Biological Macromolecules, Fiber Diffraction, General Interest, Industrial, Materials Science, Neutron Scattering, Powder Diffraction, Service Crystallography, Small Angle Scattering, Small Molecules, Synchrotron Radiation and Young Scientists. Members may join as many of these as they wish. Each Scientific Interest Group is responsible for organizing sessions at National Meetings at least every other year.