In electronic commerce, a satisfying buyer experience is a key competitive element. We show new techniques for better adapting interaction with an electronic catalog system to actual buying behavior. Our model replaces the sequential separation of needs identification and product brokering with a conversion in which both processes occur simultaneously. This conversation supports the buyer in formulating his or her needs, and in deciding which criteria to apply in selecting a product to buy. We have experimented with this approach in the area of travel planning and developed a system called SmartClient Travel which supports this process. It includes tools for need identification, visualization of alternatives, and choosing the most suitable one. We describe the system and its implementation, and report on user studies showing its advantages for electronic catalogs.