A computer implemented method of securing information stored in an entity relationship database system comprising at least one entity relationship database, the information stored in the entity relationship database system being stored according to an entity relationship model, the method comprising the steps of: specifying access rules limiting access to the entity relationship database system; storing the access rules in the entity relationship database system according to the entity relationship model; permitting an accessor to create an entity in the entity relationship database system if a “create-check” process dependent upon at least one of the one or more stored access rules grants permission; and permitting the accessor to read or modify or delete an entity stored in the entity relationship database system if a “non-create-check” process dependent upon at least one of the one or more stored access rules grants permission.