This is so you can demonstrate that you understand the problem the customer wants solved. The introduction sets the tone for the rest of the proposal. A poorly written introduction can ruin your image as a professional organization. A good way to begin a proposal is to promise to benefit the customer's need. Without repeating the wording in the RFP, state the customer's problem in clear, simple English.
Most proposals begin the introduction by describing the proposing organization.
When you choose this approach, quickly demonstrate how your firm is the logical choice for the job. The second major portion of the proposal is the discussion section. This is where you will present the logical arguments to convince the customer to give you the contract. Consider a proposal to be a sales effort and follow the logic of all good sales efforts. The introduction should get attention and the discussion section should arouse interest.