Territorial autonomies are increasingly implemented as tools for regulating ethnic conflicts. Since there are successful as well as failed cases, the ongoing debate about a general conflict-solving potential is not a very fruitful one. The article turns towards the analysis of various factors affecting the success of conflict regulating autonomies. It is argued that successful conflict regulation highly depends on the scope of self-rule transferred to a rebelling group. It offers two approaches to measure the scope and success of autonomies and introduces the Autonomy Scope Index (asi). The relevance of the degree of autonomy is tested on the basis of a global data set on all conflict regulating autonomies since 1945 by using Qualitative Comparative Analysis (qca). The study shows that a substantial degree of self-rule is indeed a crucial condition.