The activities of the Institute are open to everyone. However the TH group can only invite, host and provide logistic support (i.e. office space, registration and access to CERN, advanced Hostel booking, etc) to a limited number of official participants, of the order of 40/week. To apply for registration as official attendee, fill the application form, before March 18, 2018. There is no registration fee. The selection of the accepted participants will take place during late March / early April, and the results will be announced shortly afterwards. Experimental members of the LHC collaborations, if CERN users, do not need to apply and are welcomed to attend the Institute events.