In accordance with embodiments, there are provided mechanisms and methods for facilitating tenant-based customization of access and security controls in an on-demand services environment in a multi-tenant environment according to one embodiment. In one embodiment and by way of example, a method includes generating, by the database system, a plurality of nodes corresponding to a plurality of tenants in a multi-tenant environment, where a node corresponding to a tenant includes data relating to the tenant. The method may further include accepting, by the database system, a plurality of security models associated with the plurality of tenants, and configuring, based on the plurality of security models, security privileges including user privileges to be assigned to the plurality of users representing the plurality of tenants.