Chapter 4 begins with an in-depth process tracing of the decisions around political party formation in Egypt after Mubarak’s ouster. We revisit the puzzling variation in party formation across the Egyptian political opposition landscape, particularly examining the decision on the part of Egyptian organized labor and pro-reform activist groups not to form political parties, tracing the link between the structure of the opposition under the Mubarak regime to the strategic incentives and organizational constraints faced by groups at this juncture. We then conduct an in-depth within-case comparison of the mobilization prior to Egypt’s 2011 elections, utilizing granular data on political parties’ specific campaign strategies and methods to trace the link between the adaptations that various groups made during the Mubarak era to the relative organizational and persuasive resources political groups had, and the mobilization tactics and strategies they were then able to use. We also specifically examine compelling evidence for common alternatives or contributing explanations for the Muslim Brotherhood’s success, and show that while these explanations certainly fill in part of the picture, they are incomplete without an understanding of mechanisms linking authoritarian legacies to the 2011 elections.