Dear Colleague, If you are planning to participate in the IRENG07, ILC Interaction Region Engineering Design Workshop http://www-conf.slac.stanford.edu/ireng07/ , please register at the workshop web site, and indicate the working group of your primary interests. The working groups will start to have their phone preparatory meetings in a week, and this registration information is needed for the conveners to focus their work. If you could not come to the workshop, but would like to contribute to preparatory meetings of working groups, please inform us. Best regards Andrei for IRENG07 LOC & IPAC