Dear colleagues, We are pleased to announce that the 4th Stochastic Geometry Days organized by the French research group GeoSto will take place in Poitiers from August 26th to August 28th, 2015. The conference will be preceded by two introductory lectures for PhD and post-doc students from August 24th to August 26th. Registration is open until May 31st. For more information, you can visit the website http://www-math.sp2mi.univ-poitiers.fr/GeoSto2015/