My foremost thanks go to my mentors, Luigi Rizzi and Adriana Belletti. My journey to the Left Periphery started in Siena when I was a master's student. I say grazie for these wonderful years in Geneva working under the ERC Advanced Grant 340297 ("SynCart"), which supported my doctoral studies. I would also like to say תודה to Ur Shlonsky for his help and the beautiful conversations about linguistic and non-linguistic subjects. I am thankful for the members of the jury who honoured me to discuss this work: grazie Cecilia Poletto, danke Elisabeth Stark and Eric Haeberli. I gratefully acknowledge all the Linguistics department of Geneva: Giuliano Bocci, Paola Merlo, Luka Nerima, Genoveva Puskás, inter alia. A special köszönöm goes to Eva Capitao. I am grateful to my colleagues, with whom I discussed my (still ongoing