Modular and open – must have an open system architecture, meaning that any module can be interface, with or detached whenever required without affecting the other modules. Some organizations will begin with buying two modules, such as accounting and sales, and then will add modules, such as CRM and SCM, as they gain confidence in their current modules. (Implementing in small pieces or phases – companies do not want to buy the entire ERP and spend years implementing twenty different modules to find that it doesn’t meet their need)