Many times product quality cannot be watched by consumers at the time of buying. By lowering the quality level, firms heighten the probability of product failure. And firms have no encouragement to provide high-quality products in the lack of warranties. So that only warranties can convince firms to provide high-quality products. Consumers are usually doubtful about product performance. They seek for assurance that the product will perform sufficiently and satisfactorily over its useful life. One way of suppliying this assurance is through product warranty. This is a service factor packaged with the product. Various types of warranties are proffered, depending on the product and the expected buyer. As an incentive instrument for producers to provide high-quality products, warranties must be broad enough. Warranty is a significant factor of marketing new products as better warranty signals, higher product quality and supplies greater assurance to customers. Warranties play an important function in the resolution of disaccords that may appear between buyer and manufacturer. Servicing warranty requires additional expenses to the manufacturer and this expense depends on product reliability, durability and warranty terms. Product reliability and durability is impacted by the decisions made during the design and manufacturing of the product. This paper surveys concept of warranty. Especially types and functions of warranty and warranty certificates. It examines the legislations about warranty certificates in the field of European Union and Turkey. Also it analyzes the differences and same points of arrangements between European Union Law and Turkish Law. This paper also highlights amenabilities of manufacturers in the context of managing new products from an overall business perspective.