This contributed volume contains fourteen papers based on selected presentations from the European Conference on Game Theory SING11-GTM 2015, held at Saint Petersburg State University in July 2015, and the Networking Games and Management workshop, held at the Karelian Research Centre of the Russian Academy of Sciences in Petrozvavodsk, Russia, also in July 2015.  These papers cover a wide range of topics in game theory, including recent advances in areas with high potential for future work, as well as new developments on classical results.  Some of these include A new approach to journal ranking using methods from social choice theory; A differential game of a duopoly in which two firms are competing for market share in an industry with network externalities; The impact of information propagation in the model of tax audits; A voting model in which the results of previous votes can affect the process of coalition formation in a decision-making body; The Selten-Szidarovsky technique for the analysis of Nash equilibria of games with an aggregative structure; Generalized nucleoli and generalized bargaining sets for games with restricted cooperation; Bayesian networks and games of deterrence; and A new look at the study of solutions for games in partition function form. The maturity and vitality of modern-day game theory are reflected in the new ideas, novel applications, and contributions of young researchers represented in this collection.  It will be of interest to anyone doing theoretical research in game theory or working on one its numerous applications.