New products are the lifeblood of marketing. Even the most successful products have a life stage, and so marketing companies are continually looking to develop new products and re-stage existing ones. It is almost universally true that the best performing companies are the ones that have the strongest track record of bringing new products to market. It is also true to say that new product development is one of the most exciting and interesting areas, both for the marketer as well as the researcher. In fact the authors believe that it is sometimes too interesting and can produce an over-concentration of effort in less profitable ventures. The inherent profitability of many marketing companies is heavily dependent on the success of a relatively small number of well-established brands. While it is certainly correct that they should always be looking for new opportunities, the less glamorous task of looking after these profitable brands will pay back considerably more in the short to medium term. It can often be the case that the brighter and more dynamic marketing executives are focused on the more stimulating area of new product development to the detriment of some existing brands and also short-term profitability. Having said this, however, there is a great need for product development within companies, and it is an area in which they constantly look to market research to help them. The rest of the chapter looks at the various stages of the product development process and the role of market research within them.