The 22 July 2011 attacks in Norway offers a rare opportunity to study in detail the factors and circumstances which influenced the decision-making of the lone actor terrorist and the target selection process in particular. The terrorist had more than 65 potential targets that were on his mind, but he included only a third of these in concrete plans, before he ended up attacking only two. Which factors made him dismiss some targets to the benefit of others, and at what time in the selection process did crucial decision-making sequences take place? What were the alternatives he considered? The study will analyse the dynamic interaction between four main components: Ideology defines the overall objectives and the enemy picture, as well as the reasoning and moral reflections that constitute the basic fundament of the actor’s rationality. Strategy is the long-term plan for how the overarching objectives are to be achieved. Furthermore, the decision-making is also influenced by internal factors possessed by the terrorist actor, such as manpower, skills, funding, weapons, psychological make-up, and external factors outside the terrorist’s control, such as counterterrorism efforts, local environment, gun control laws or unexpected events.