structural:scholar_edition, linguistic:paraphrasing, quality:correction
Conversion and deconversion

Rastafari is a non-missionary religion. However, elders from Jamaica often go "trodding" to instruct new converts in the fundamentals of the religion. On researching English Rastas during the 1970s, Cashmore noted that they had not converted instantaneously, but rather had undergone "a process of drift" through which they gradually adopted Rasta beliefs and practices, resulting in their ultimate acceptance of Haile Selassie's central importance. Based on his research in West Africa, Neil J. Savishinsky found that many of those who converted to Rastafari came to the religion through their pre-existing use of marijuana as a recreational drug.

Rastas often claim that—rather than converting to the religion—they were actually always a Rasta and that their embrace of its beliefs was merely the realisation of this. There is no formal ritual carried out to mark an individual's entry into the Rastafari movement, although once they do join an individual often changes their name, with many including the prefix "Ras". Rastas regard themselves as an exclusive and elite community, membership of which is restricted to those who have the "insight" to recognise Haile Selassie's importance. Practitioners thus often regard themselves as the "enlightened ones" who have "seen the light". Many of them see no point in establishing good relations with non-Rastas, believing that the latter will never accept Rastafari doctrine as truth.

Some Rastas have left the religion. Clarke noted that among British Rastas, some returned to Pentecostalism and other forms of Christianity, while others embraced Islam or no religion. Some English ex-Rastas described disillusionment when the societal transformation promised by Rastafari failed to appear, while others felt that while Rastafari would be appropriate for agrarian communities in Africa and the Caribbean, it was not suited to industrialised British society. Others experienced disillusionment after developing the view that Haile Selassie had been an oppressive leader of the Ethiopian people. Cashmore found that some British Rastas who had more militant views left the religion after finding its focus on reasoning and music insufficient for the struggle against white domination and racism.