TERMS OF REFERENCE The main topics addressed by TC204 concern the geotechnical aspects of the design, construction and analysis of deep excavations, tunnels and large underground structures, with particular emphasis on the development, effects and control of ground movements, their interaction with existing structures, mitigation measures and risk management. In this field the objectives for the period 2010-2013 are as follows. 1. To disseminate knowledge and practice in the field of underground construction1.1. At an international level- To organise the seventh International Conference on “Geotechnical Aspects of Underground Construction in Soft Ground” in Roma, 16-18 May, 2011.- To prepare the organisation of the eighth International Conference on “Geotechnical Aspects of Underground Construction in Soft Ground” in 2014.- To promote a session or a workshop during the next ICSMGE, Paris 2013.- To actively encourage the preparation of papers from TC204 members to be published in refereed journals and in particular for the ISSMGE International Journal of Geo-Engineering Case histories.1.2. At a regional level- To organise regional workshops at the occasion of large or challenging projects: Crossrail in London, Toulon road tunnel, others to be defined.- To encourage the active participation (papers, lectures, workshops) of TC204 members at regional conferences.2. To establish guidelines and technical recommendations2.1. To edit a list of codes and guidelines existing worldwide in the field ofgeotechnical aspects of tunnelling.2.2. To report during the TC204 Roma International Symposium on the three workinggroups launched by TC28:- database to store information about underground construction projects;- guidelines for comparing field observations with numerical simulations;- survey on design practice in the field of soft ground tunnelling.2.3. To launch a working group on seismic behaviour of tunnels.3. Interact with other TCs and organisations concerned by underground construction:3.1. Proposal of an invited lecture from TC214 “Soft soils” during the TC204 Romasymposium3.2. To cooperate with TC104 “Physical modelling” to extend the guidelines forcomparing field or physical model observations with numerical simulations.3.3. To establish or maintain contact with TCs having close interests such as TC206,TC207, TC305.3.4. To make contact with ITA for defining fields of possible cooperation and to investigate the possibility of creating a common Working Group.