Political opportunity concepts or perspectives seek to explain the emergence trajectory and outcomes of a movement by examining its political milieu. Therefore, analyses using this concept are working on this premise that "exogenous factors enhance or inhibit a social movement's prospects for (a) mobilizing, (b) advancing particular claims rather than others, (c) cultivating some alliances rather than others, (d) employing particular political strategies and tactics rather than others, and (e) affecting mainstream institutional politics and policy." It is now also widely accepted in the literature that political opportunities and threats are perceptions that protestors attribute to their political. However, while the subjective aspect of opportunities and threats is recognized in the literature, the issue of disagreement over opportunities and threats is downplayed in the literature. In fact, it is possible that different actors within the field of a social movement disagree over opportunities and threats for movement. I shall also argue that movement actor's assessments of opportunity and threat involve their theories of history and socio-political change, in that actors analyze their political context through these theories. Besides, agreement is disagreement over these perceptions is important in the coalitional dynamics of the movement. Diverging and converging perceptions of opportunity and threat matter for the disintegration and formation of coalitions within movements. The Iranian Reform Movement (1997-2005) might be an interesting case in which to study disagreement over political opportunities and threats. The Iranian reform won the presidential elections in 1997 and 2005, won the municipalities in 1998 and legislature in 2000 and lost them in turn in 2005, 2002, and 2004. In all these eight years there were different debates within the movements about threats and opportunities for movement. While one side including president Khatami and his allies considered radicalism and mass mobilization as threats for the movement, there were other important individuals and political groups within the movement criticizing the former for missing opportunities for more radical break and more aggressive strategies for proceeding reforms. My data consist of three main parts. The first part includes interviews and articles from different active members of the reform movement between 1997 and 2005. The second part of data is interviews that I conducted with five prominent members of the reform movement during the summer of 2007. The third part of data is made up of interviews and articles of the movement members after 2005.