The International Solving Contest began in 2005 and is an annual solving event which takes place usually on the last Sunday in January. It is run simultaneously at multiple venues in many countries. There are three sections, an Open section, a section aimed at less experienced solvers, featuring easier problems, and a section for juniors. The normal format of the Open section consists of two sessions, each lasting two hours and featuring six compositions of differing types. John Nunn has been the most successful British solver, winning the event in 2011 and 2017.