In the classical period of Islam, the term ijtihad was part of a longer formulation, namely: ijtihad bi al-ra’y, which means ‘putting in utmost effort in the exercise of personal reasoning and analogy’.
It is often assumed that ijtihad is practiced by Shi‘is and that the gates of ijtihad have been closed in Sunni Islam. Recent scholarship has challenged the later part of this assertion. However, little research has been done on the history of ijtihad in Shi‘ism. This chapter will examine the development and gradual deployment of ijtihad by Shi‘i jurists. It will be seen that most of the early Shi‘i jurists rejected ijtihad and that the vacuum created by the occultation of the Imam plus the necessity to respond to the community’s increasing needs forced the jurists to invoke principles of ijtihad in Shi‘i Islam.