The 12th Synthesis Imaging Workshop will be held June 8-15, 2010 at the NRAO and New Mexico Institute of Mining and Technology in Socorro, NM. The Workshop will comprise a week of lectures on aperture synthesis theory and techniques at a level appropriate for graduate students in astrophysics. The Workshop will also include two days of practical tutorials demonstrating data collection, calibration, and imaging of various types of data, including new data from the EVLA and VLBA, and a millimeter/submillimeter wavelength dataset. More information on scheduled lectures and events is available online. If you are interested in receiving more information about the workshop, please pre-register on the same web page. A formal first announcement will be distributed in early 2010.