This conference is the main event in the field of three-dimensional structure determination of biological macromolecules by electron cryo-microscopy. 3DEM is a key technique in structural, molecular and cell biology, and encompasses a wide range of biologically important structures from macromolecular assemblies and viruses, regular helical arrays and monolayer crystals of membrane proteins, to 3D imaging of whole cells or sections by electron tomography. The resolution achieved ranges from molecular in electron tomography to near-atomic in the case of regular arrays. Even with non-crystalline particles a resolution of 3Å, at which accurate molecular models can be built, is now within reach. Electron microscopy holds great promise for technical improvements that will widen its scope I biology even further. Significant advances in image contrast and signal/noise ratio are likely to result from advances in the design of new, sensitive electron detectors and devices such as phase plates and aberration-corrected lenses, which are now becoming available. Added to this, continuous improvements in image processing procedures used to calculate 3D volumes from projection images make it possible to classify and resolve different functional states of macromolecules. The 3DEM Gordon Research Conference has a distinguished record of bringing together pioneers in technology development and world-leading experts in the most advanced biological applications. In response to greatly increased demand, the conference is being held annually, with alternating meetings in New England and Europe. The next 3DEM GRC will be held on 15 - 20 June 2008 in Il Ciocco, Barga, Italy, in an pleasant hillside location in Northern Tuscany, within striking distance of the historic cities of Lucca, Pisa, and Florence. The program offers an attractive combination of lectures, poster sessions, workshops and free interaction time. Attendance will be limited to ~150 participants, early registration is recommended.