The main goal of this thesis is to explore how Online Social Networks (OSNs) can support users in managing their online reputation during important selection processes. More specifically, we look at mechanisms that help social media users automatically dissociate from their past online activities, primarily in a hiring context. I would like to begin by thanking my thesis supervisor, Sonia Chiasson, for her continuous support. She has been a great example and a role model to me, on both a personal and a professional level. She always made herself available and provided unlimited advice. As someone with a high level of knowledge and a broad spectrum of expertise, Prof. Chiasson has given me invaluable guidance throughout the duration of my degree and I am deeply indebted to her. I would also like to thank my defence committee, Pamela Briggs, Daniel Amyot, Audrey Girouard, and Andrew Patrick. They have provided me with useful guidance and valuable feedback that helped inform various parts of the thesis. I am also grateful to my parents and my brothers. I would like to thank them for believing in me and for always encouraging me to achieve my goals. Although they are so far away, they never ceased to give me the emotional support and encouragement I needed. I would not have been able to complete this work without their support. I thank Thaís Bardini Idalino for being dedicated in our collaborative study. I am happy to have worked with such a smart woman. I also thank Khadija Baig for being such a dedicated researcher. I am grateful for her effort and time spent on transcribing interviews in one of the Chapters, and for her emotional support. Similarly, I am grateful to Paulina Chametka for her help in various tasks, including running interviews, audio transcription, and data analysis. I appreciate her time and effort.