You should by now understand that integrating the various functions within a manufacturing plant's operation requires that manufacturing people (responsible for how we make it, how much inventory is needed, how much labor is required) work closely with the sales and marketing folks (responsible for what the product should look like, how it is packaged, promoted, who will buy it, how many will be sold, at what price, etc.) and in close concert with the financial people (responsible for costing, capital and financial management in general).
While computer systems greatly enhance the capabilities of having real time, on-line, organized data available to the enterprise, it is worthless unless people from various backgrounds and disciplines work together toward accomplishing the same goals and objectives.
This kind of teamwork has proven itself in new product development initiatives where engineers, production people, sales people, marketers, and financial people are linked from the inception of a new product to its ultimate delivery to the customer. The result has been drastic reduction in the time it takes to bring a product to the market place.