The main goal of the 3 years Doctoral Programme is the formation of young researchers in Experimental Physics. The student is expected to acquire a broader cultural background in Physics, to get specific skills in traditional and state-of-the-art experimental techniques, and to develop a critical sense in the analysis of the data and in the interpretation of science results. This is made possible by an active participation of the PhD student in international projects financed by the EU and/or by italian research institutions (INFN, CNR, MIUR, ASI). Specific R&D research projects provide the opportunity to get hands-on experience in the design and implementation of innovative instruments requiring specific know-how in microelectronics, opto-electronics and data acquisition. The physics research groups of the Univ. of Siena are well integrated in large international research collaborations including: High Energy Physics (CDF, CMS, TOTEM) with experiments at particle colliders (CERN, FNAL); Astroparticle Physics (CALET, MAGIC) with experiments in space (on the International Space Station) and ground observatories; Photonics (Quantum Optics) at Legnaro INFN National Laboratory; Complex Systems; Medical Physics. This allows our PhD students to access the experimental facilities provided by leading national and international laboratories, universities and research institutions via research stages abroad. The board of school (21 professors + 6 researchers) includes 5 tenured professors from foreign universities. PhD thesis in co-supervision are regulated by international agreements. Lessons and seminars are in English.