A "prerequisite" is something that must be completed or achieved before something else can happen or be learned. It is a necessary requirement or condition that must be met first. Full definition
Secure attachment is a necessary but not sufficient prerequisite for becoming a cooperative, valuable and accepted member of one's group and society. (child-encyclopedia.com)
The conviction that moral standards are not arbitrary, that they reflect basic human truths and therefore that they must be passed from generation to generation is a necessary prerequisite of all moral education. (educationnext.org)
Please be advised this is considered an advanced level training and it is recommended to have plenty of experience in personal practice as well as a foundation training as prerequisite. (vikasayoga.com)