Potential vendors responding to RFPs may be characterised as "responsible" and/or "responsive". A "responsible bidder" is one who is qualified or capable of meeting the requirements set out by the government in its bid solicitation or RFP. Kate Manuel notes that the concept of responsibility on the part of a bidder "has been the federal government’s policy since its earliest days". James F. Nagle, in his "History of Government Contracting", describes how Robert Morris made contract awards to the lowest-priced qualified responsible bidder in contracting for the U.S. Army during the Revolutionary War.