The paper focuses on the opinion of the jurists about the concept of baghy and its significance in Islamic law. The objective of this paper is to provide a comprehensive review of the issue of baghy, and the thinking of Ibn Taymiyya within the context of jihàd. The paper starts with a brief explanation of the lexical meaning of baghy and its position in classical texts. The paper continues with a discussion about the legal status of baghy in Ibn Taymiyya's view. Later, it attempts to shed some light on the issue of baghy and jihàd against unjust or corrupt imàms, and what is the relationship between them from the perspective of the two prime sources of Islam: the Qur'an and hadith, with special focus on Ibn Taymiyya's point of view. This topic is treated in detail in the present study, and most of this problem is as pertinent to the umma today as it was in the time of Ibn Taymiyya. It is hoped that the following exposition will have some valuable impact on the on-going debate about baghy and jihàd. It bears noticing, however, that this paper is only concerned with the views of the jurists of the four major Sunni schools. The views of other schools, including Shia, although interesting, will not be discussed.