In most cases, a law firm must conduct an extensive factual investigation in order to determine if a client was injured as the result of a defective product. Three types of product liability are manufacturing defects, where poor workmanship of the individual item or materials causes an injury, design defects, where the design of the product is inherently dangerous (for example, a certain safety feature should be included on the item), or duty to warn, which is where there is no or inadequate warning that a product may be dangerous. Proving product liability is often difficult. If you feel you have been injured because of the way a product is made or marketed, then you may be entitled to compensation for your injuries, and you should contact a lawyer.