To do the proper job for a company there is a lot of detail required to ensure the customer gets the right product, at the right time, in the right quality, and in the right quantity. There are several ways to effectively specify the item required.

When an Industry Standard is available:

Referencing standard items or services is a common method of determining specifications. A half-ton truck is a standard industry specified item that is the same across all manufacturers. Doing an oil change is a standard or industry specified service. A part number or service number is also a way to describe an item or service. When items or services have references, there is no need to specify quality, size, colour, etc. and these attributes are already know to both parties.

When no Industry Standard is available:

If the product or service has been previously purchased the original purchase order or service contract can be used as a reference. This way the buyer, the seller and the end user are clearly identifying the same item or service and have the same expectations.

If the product or service has not been previously purchased, the item or service must be specified from the very basics. Many products have specifications that are measurable - size, shape, colour, weight, etc., and may also have performance based specifications.