Ijma is an important mode of Ijtehad and well known principle of Islamic Sharia. Historically it is evident that incidence of IJMA/Consensus restricted only to four Caliphates of Islam only. Many jurists and scholars denied its incidence absolutely and some others have been of the opinion that it is only restricted to Medina, Basra, Kufa. Some restrict it to Ahl-e-Bait only. In this paper it is concluded after the academic discussion and analysis of the opinions of many experts of Islamic Jurisprudence; 1-Actually the consensus on many legal issues in the period of companions of the Holy Prophet was with mutual consultation and basically it was the "Collective Ijtehad", which had been known as "IJMA" at that time. The term "Collective Ijtehad", was not in use at that time.2- This Collective Ijtehad and Collective Opinion was actually the decision of the Islamic State followed and obeyed by the all Muslims specially by "SAHABA", so why it's called Ijma-e-Sahaba.3- These decisions were applicable and binding to all Muslims living elsewhere in the world, because at that time there was centralized ruling system (Khalafat-e-Wahida).4-Now Muslim world has split into many states, so every state has its own decision making institutions and hence such Ijtehad and Ijma/Islamic Legislation Activities should be validated within those states as Ijtehad and Ijma except issues relevant to general interest as whole human being and all Muslims. In such issues International level consensus of Islamic Jurists would be required. In the paper it is also concluded that "Collective Ijtehad" should be dealt as "IJMA", actually it is the same processes. More over any "Ijma" / Consensus held in a time period can be revoked by any new situation in future as per requirement of the time. It is the inevitable demand of dynamism of Islam to correlate it to every need of the time.