A Request for Proposal (RFP) is the formal document used by an agency to solicit services from the outside sources that education agencies often use for the design, administration, or scoring of assessment measures. The guidelines presented are intended to help in writing an RFP. A few fundamental aspects of assessment significantly influence the planning of the RFP process and document: money; time; nature of the project; type of bid; and phases of the project. Because the RFP is part of the eventual contract it should be as clear and precise as possible. Constraints typically hindering the development of "good" RFPs include limitations imposed by agency policies and procedures; limited communication between the agency and bidders; and concern for cost, sometimes at the expense of quality. To deal with these constraints, the RFP writer should specify as carefully as possible what is desired and expected; encourage fair and timely communication with the bidders; and build control of technical quality into the RFP and the project. (SLD)