Alisna Specializes in Plant Design / Engineering software tools and Business process optimization. "..... people and departments cannot perform their tasks in isolation and one activity cannot simply finish and the next activity start. Design is an iterative process, often designs need to be modified due to manufacturing" and construction "constraints or conflicting requirements. Where a customer order fits into the time line depends on the industry type and whether the products are for example, built to order, engineered to order, or assembled to order." http://en.wikipedia.org/wiki/Product_lifecycle_management