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\section{\ref{sec:conclusion} Conclusion}  \label{sec:conclusion}  The discoveryof the H(126) particle  at the LHC of a particle that resembles strongly the long-sought Higgs boson of the Standard Model  has focused placed in a new perspective  studies for the next large  machineneeded  for high-energy physics. While brand-new ideas are emerging for future Higgs factories, the The  prospects for the next decade already look quite promising: the HL-LHC isindeed  an impressive Higgs factory, with great potential for measuring many  Higgs boson coupling measurements to couplings with accuracies of  a few per-cent accuracy. per-cent.  The LHC  run at 13-14 TeV may well  discover something else, unfortunately likely to and it would  be beyond premature to mortgage the future of high-energy physics before knowing what it reveals. In  the ILC reach. mean time new ideas are emerging for possible future Higgs factories.  Beyond In view of  the HL-LHC, it is now generally accepted that financial, technical and personal resource needs for the next large high-energy physics machine,  it is important essential  to choose the right machine, as not machine that is complementary  tomortgage the future of the discipline with a suboptimal choice (given the cost of these machines). To cut a long story short,  the right machine must bring orders of magnitude LHC,  with respect to optimal capabilities beyond  what can be achieved at LHC, both with HL-LHC,  in both  precision measurements and in and/or  discovery potential.As alluded to in this article, it turns out that the ILC project has neither of these capabilities, with both too small a luminosity and too small a centre-of-mass energy.  Instead, In our view, TLEP,  a large $\epem$ circular collider seems in a tunnel with 80  to be the 100~km circumference, would  best complement to the  LHC, with as it would provide  {\it (i)}a  per-mil precision on in measurements of  Higgs couplings; couplings,  {\it (ii)} an unbeatable unique  precision on EWSB in measurements of electroweak symmetry-breaking  parameters andon  the strong coupling constant; constant,  {\it (iii)} a measurement of the number of active neutrinos neutral particles equivalent  to better than 0.001; 0.001 of a conventional neutrino species, and  {\it (iv)} a unique search programme for rare Z, W, Higgs, and top decays; and {\it (v)} a very competitive cost. Circular decays. We emphasize that circular $\epem$  colliders have also the most use a  mature technology: they are supported by technology that has been developed during the  progress of successive  $\epem$ factories for 20 years, and it turns out machines over 50 years. Many of the key technical advances  that make TLEP possible will be demonstrated by  SuperKEKB, with which has many  parameters similar to TLEP, TLEP. Experience with SuperKEKB  will be a precious demonstrator. Based on this experience, make possible more reliable estimates of  the cost,the  power, andthe  luminosity predictions will be reliable. Most importantly, for TLEP. Moreover,  TLEP is also would be  a first step stepping-stone  towards a 100 TeV pp collider in the same tunnel,  and therefore provides  a unique long-term vision for high-energy physics.The design study of TLEP has now started, in close collaboration with the VHE-LHC design study, with worldwide collaboration from Asia, USA and Europe, and with full support from the CERN Council. The study is now acted in the approved CERN Medium-Term Plan (2014-2018). The first proposed step is a design study report in 2015, towards a conceptual design report and a detailed cost estimate in 2018-2019, for an informed decision to be taken in full knowledge of the LHC results at 13-14 TeV. A solid backbone exists for both the design and the rich, albeit demanding, physics case of TLEP.     We aim for physics in 2030.  The design study of TLEP has now started, in close collaboration with the VHE-LHC design study, with worldwide collaboration from Asia, USA and Europe, and with full support from the CERN Council. The study is now included in the approved CERN Medium-Term Plan for the years 2014-2018. The first proposed step is a design study report in 2015, be followed by a conceptual design report and a detailed cost estimate in 2018-2019. In this paper, we have provided a first look at the possible physics of TLEP, which may serve as a baseline for exploration of its rich physics possibilities during this period. An informed decision on the project could then be taken in full knowledge of the LHC results at 13-14 TeV and operational experience with SuperKEKB. Technically, TLEP could be ready for physics in 2030, if given the necessary financial and political support.