This study attempted to carry out an overview of the Yussufiyya Boko Haram sect and its activities in Nigeria. Secondary data obtained mainly from National newspapers and the internets were used in the analysis. It was revealed that the sect emerged mainly as a reaction to western value system which was believed to have polluted our culture. Boko Haram which was once a social communal movement gradually metamorphosed into a vicious sect operating in some states of the north-east of Nigeria. The study also showed that Boko Haram had a dream of establishing a kind of Utopian egalitarian society and to achieve this task, recruited gullible youths to stage a Jihad in an attempt to Islamize, at least the northern part of Nigeria. The sect in recent past has evolved and proliferated to such a frightening point that it could engage the Nigerian military in full-blown confrontation in an attempt to pursue its ruthless expansionist ambition. This ambition has however, been significantly checked as the sect has been technically defeated and restricted to the sambisa forest. It is recommended among others that government should continue to use the carrot and stick approach in handling the insurgency while making attempts to have an understanding of the sect‟s ideology as this will assist in the deradicalisation process.