In an embodiment of the invention, wherein users must be able to access a computer system to perform respective functions, initial data is acquired from data sources, some of the initial data pertaining to previously granted system access rights. The initial data is used to create a crowdsourcing task, which is executed to acquire crowdsourced data from SMEs in an SME population, wherein the crowdsourced data comprises additional data pertaining to previously granted system access. The crowdsourced data is used to create a set of role definitions, wherein the role definitions determine which of the users are assigned to be members of a particular role associated with the system, and further determine the access rights that are granted to each member of the particular role.