The last twenty years have seen the growth and development of an alternative approach to the history of technology: contextualism. John Staudenmaier has defined contextualism as a methodology which combines design with ambience - contextualist scholars study the technical characteristics and constraints of a particular technology (design) in relation to the economic, social, and political contexts (ambience) in which they emerge and develop. All contextualists historians of technology do not bring the same approach to their studies, however. We identify two basic approaches. The first treats technology as expanding knowledge, the second characterizes technology as a social force or a social product. We review four recent major works in the history of technology which exemplify the contextualist trend. Each of the authors, Thomas Highes, David Hounshell, David Noble, and Ruth Cowan, occupies a unique position on the spectrum between the two basic approaches to contextualism.