Another endorsement, this time from eminent Crowley authority Richard Kaczynski:

In addition to gifting us with a long-needed anthology of Aleister Crowley’s group rituals, Rodney Orpheus’ “Grimoire,” with its inclusion of rituals *inspired* by Crowley, is also a course on how to take older texts and adapt them to one’s needs.  The cookbook-style “list of ingredients and preparation time” that precedes each ceremony handily gives aspiring ritualists a heads up on how many Fratres or Sorores are needed, how much memorization is required, and how complex the ritual equipment and staging is.  Eminently readable and (most importantly) *usable*, “The Grimoire of Aleister Crowley” will keep many a magical group busy for years to come.