In her dissertation, Aalen explores how the national political framework of ethnic based federalism is implemented in two local communities (Sidama and Wolayta) in the multi-ethnic region of Southern Ethiopia (SNNPRS) in the period from 1991 to 2006.

It is undisputable that EPRDF's introduction of the ethnic based federal system in 1991 represents a particularly important impetus to these communities' continuous construction of ethnic identities. By the establishment of fixed and easily distinguishable ethnic political and administrative units, the political system has institutionalised the politics of ethnicity and attempted to arrest the fluidity and flexibility that ethnic identities represent.

Through the methodology of comparative case study research of Sidama and Wolayta, it has however been revealed that the political mobilisation under ethnic federalism has produced different patterns of political behaviour: in Sidama it has led to internal political/ identity fragmentation, while in Wolayta it has consolidated and strengthened the politico-ethnic identity.

In contrast to the institutional approach in political science, which forwards the view that institutional design is the main determinant of political behaviour, the contradictory cases of Sidama and Wolayta demonstrate that even if communities go through the same type of institutional reform, they are likely to produce different sets of political outcomes.

My empirical material from Southern Ethiopia display therefore that there is no one-directional or mono-causal relationship between the introduction and functioning of federal systems and the nature of ethnic political mobilisation - federal institutional arrangements, isolated from all other political processes, cannot produce predictable or uniform changes in the relationship between ethnic groups.

In this dissertation, I have therefore proposed an alternative to the institutional approach. Instead of assuming that it is first and foremost institutions per se that determine political behaviour, institutional change should be analysed within a wider web of factors. In the analysis of historical trajectories, majority-minority relations, party formations and specific controversies fed by ethnic claims within Sidama and Wolayta, it is found that ethnic political mobilisation not only express strains in the relationship between different ethnic groups, but are equally reflecting struggles between sub-groups within the ethnically defined communities.

This dissertation suggests therefore that ethnic political mobilisation must be understood as an outcome of both inter-ethnic and intra-ethnic relations.