The European Crystallographic Association www.ba.cnr.it.eca/ has active Special Interest Groups in the areas of Macromolecular Crystallography, Aperiodic Crystallography, Mineralogical Crystallography, Instrumentation and Experimental Techniques, Crystallographic Computing, Charge, Spin and Momentum Density, Electron Crystallography, Powder Diffraction, Molecular Interaction and Recognition. National members of the ECA include Austria, Belgium, Bulgaria, Croatia, Czech Rep., Denmark, Egypt, Estonia, Finland, France, Germany, Hungary, Israel, Italy, Latvia, Netherlands, Norway, Poland, Portugal, Russia, Serbia, Slovakia, Slovenia, S. Africa, Spain, Sweden, Switzerland, UK, Ukraine.