Problems in the process of conversion from the Voice of Customer (VOC) to technical character of product using the House of Quality (HOQ) are analyzed, and a statistics-based quantifiable technique for product definition is developed to benefit adaptive design. With the underlying principles of HOQ, e.g. customer orientation and integration of marketing and engineering, this technique assures quality in concept design by means of various tools such as Design of Experiments (DOE) and Conjoint Analysis. The principles of the tools used are introduced briefly, and the realization process of the technique is discussed in detail with an example of the concept development of a minivan as its demonstration.