Workshop on Particle Accelerators The workshop has been held at Varenna which is undoubtedly one of the most beautiful and characteristic villages in the eastern bank of Como Lake. The mild climate and the picturesque surroundings guarantee a relaxing and peaceful stay. Villa Monastero, one of the most ancient and famous villas of the region with its impressive botanic garden, is one of the worldwide best known tourist attractions. Once a monastery, and then transformed into a residential palace, the Villa is now administered by the Province of Lecco. Topics Challenges and perspectives of the European Spallation Source The European X-FEL Diffraction Limited Storage Ring Swiss Light Source: the next 20 years Elettra and FERMI perspectives Extreme Light Infrastructure - Nuclear Physics Plasma accelerators: present status, future developments and applications The diffraction-limited storage ring frontier Future Circular Collider (FCC) High-Luminosity LHC Challenges and opportunities of high intensity Gamma photon sources Current status and Future Development of Light Sources in China Accelerator Projects in Korea: current status and perspectives Accelerator based research infrastructure in the US, present status and future developments ILC status and perspectives After the Higgs discovery: perspectives on HEP Scientific perspective and applications of X-ray FEL radiation Perspective for Nano-meter 3D-resolution from coherent scattering imaging at synchrotron and XFELS Layout and opportunities with SwissFEL Free Electron Laser based multicolor spectroscopy Emerging science opportunities with coherent, high-energy x-rays Structural biology: from large crystals to single molecule imaging. Status and future accelerator based infrastructure requirements Advances and perspectives of X-ray imaging for Cultural Heritage Status and perspectives of bio-medical and medical research with accelerators New research horizon in hadrontherapy Catalysis research with advanced X-ray techniques in SSRF: Present and future challenge Participation fee: 350,00 (VAT included) for attendance, half board and one dinner party.