Now that the three-year-long PhD period of intense learning and challenging myself has finished, I want to reflect on those whose aid has made-one way or another-this thesis possible. Foremost, I would like to express my sincere gratitude to my supervisor, Prof. Alessandro Colombo, whose careful guidance was of particularly great use for me in the beginning, when I was having difficulties with finding a good research path. It is largely the merit of his being demanding that working on this thesis has greatly contributed-as least, as it seems to me-to the advancement of my analytical and critical thinking skills, helped me develop an eye for details, pay more attention to wording and formulation, routinely verify all data and sources and not jump to conclusions. As my research proceeded, I gradually got increasingly able to perform most analysis by myself with less and less dependence on Prof. Colombo's supervision. For this, I would also like to give due credit to him, remembering educational theorist Thomas Carruthers' famous quote describing a good teacher as "one who makes himself progressively unnecessary." Moreover, I have presented parts of this research at various occasions-conferences, workshops and colloquia-where a number of people reflected on my talks, giving me helpful suggestions. Among such, I would like to highlight the contributions of Andrea Carati, Corrado Stefanachi, Simone Dossi, Nicolò Raico, Andrea Locatelli, Fabio Franchino, Marco Clementi and Giampiero Cama. I especially gratefully acknowledge Peter van Elsuwege, John Gaventa and Francesco N. Moro, the discussants who read and made useful comments on my-often ill-edited-conference papers. I would like to express my particular appreciation to Michele Chiaruzzi and Sonia Lucarelli for their elaborate suggestions on an earlier draft of this thesis. Also, my sincere thanks goes to Francesco Capuzzi, Angelica Puricelli, Giovanni Gentili and Mirele Plenishti, my fellow students who have become my good friends and without whose immense support I would have hardly survived in Milan with my poor knowledge of Italian, especially during the first year. I am particularly indebted to Mirele who kindly reviewed two versions of my research proposal and translated this thesis' abstract into Italian. Finally, I thank Università Cattolica del Sacro Cuore di Milano for financing my Acknowledgements iv research and all the members of NASP's Board and Steering Committee for the overall organisation of our PhD program. My special appreciation goes to the program's coordinators, Prof. Francesco Zucchini and Licia C. Papavero, for their invaluable assistance with multiple administrative and organisational issues which I have encountered living in Italy.