What is Request For Information?

Legal Definition
A request for information (RFI) is a standard business process whose purpose is to collect written information about the capabilities of various suppliers. Normally it follows a format that can be used for comparative purposes.

An RFI is primarily used to gather information to help make a decision on what steps to take next. RFI's are therefore seldom the final stage and are instead often used in combination with the following: request for proposal (RFP), request for tender (RFT), and request for quotation (RFQ). In addition to gathering basic information, an RFI is often used as a solicitation sent to a broad base of potential suppliers for the purpose of conditioning suppliers' minds, developing strategy, building a database, and preparing for an RFP, RFT, or RFQ.

The ubiquitous availability of the Internet has made many government agencies turn either to state-run or vendor operated websites which provide listings of RFI's as well as RFPs and RFQ's. Many allow vendors to sign up at no charge to receive e-mails of requests either generally or for specific categories of product or service for which there is an interest. In some cases, the entire process is done on-line with responses as scanned documents or PDF files uploaded to the server; in other cases, or for legal reasons, a response must be sent in hard copy form and/or on CD/DVD disc or flash drive by mail or delivery service.
-- Wikipedia
Legal Definition
The request for more input by the project planners where specific items have not been listed.