Purchasing Managers, buyers, and purchasing agents buy a vast array of farm products, durable and nondurable goods, and services for companies and institutions. They attempt to get the best deal for their company—the highest quality goods and services at the lowest possible cost. They accomplish this by studying sales records and inventory levels of current stock, identifying foreign and domestic suppliers, and keeping abreast of changes affecting both the supply of, and demand for, needed products and materials. Purchasing professionals consider price, quality, availability, reliability, and technical support when choosing suppliers and merchandise. To be effective, purchasing professionals must have a working technical knowledge of the goods or services to be purchased. There are several major types of purchasing managers, buyers, and purchasing agents. Wholesale and retail buyers purchase goods, such as clothing or electronics, for resale. Purchasing agents buy goods and services for use by their own company or organization. Purchasing agents and buyers of farm products purchase goods such as grain, Christmas trees, and tobacco for further processing or resale. Purchasing managers usually handle more complicated purchases and may supervise a group of purchasing agents. Purchasing professionals employed by government agencies or manufacturing firms usually are called purchasing directors, managers, or agents; sometimes they are known as contract specialists. Purchasing professionals in government place solicitations for services and accept bids and offers through the Internet. Some purchasing managers, called contract or supply managers, specialize in negotiating and supervising supply contracts. The duties of Purchasing Manager includes to evaluate suppliers based on price, quality, and delivery speed, Interview vendors and visit suppliers' plants and distribution centers to examine and learn about products, services, and prices. They also attend meetings, trade shows, and conferences to learn about new industry trends and make contacts with suppliers. They also analyze price proposals, financial reports, and other information to determine reasonable prices And negotiate contracts on behalf of their organization. It also involves work out policies with suppliers, such as when products will be delivered and they also need to meet with staff and vendors to discuss defective or unacceptable goods or services and determine corrective action and evaluate and monitor contracts to be sure that vendors and supplies comply with the terms and conditions of the contract and to determine need for changes. Purchasing manager also need to maintain and review records of items bought, costs, deliveries, product performance, and inventories.