The 23rd International Symposium on Nuclear Electronics and Computing (NEC-2011) starts on Monday 12 September 2011 in Varna. About half a century passed away after the first conference in Dubna (1963) showed dramatic growth of this field of science. Leading JINR scientists, their colleagues from Europe and the USA will present reviews and reports. The Symposium is intended for encouragement of further development of research in the fields of nuclear electronics and computing for physics research, and closer cooperation between JINR, CERN and INRNE of the Bulgarian Academy of Sciences, which is a co-organizer of the Symposium. A numerous group of young specialists from countries of the Central and Eastern Europe participate in the Symposium.