# Using, designing and plans (Chapter 2 of Vermaas and Houkes Book) **Opening (not a real abstract):** Using, designing and plans We start this book by presenting the action-theoretical background for our theory of technical functions. To this effect, we study two commonplace actions that involve artefacts: using and designing. We analyse both of these activities in terms of one central concept, that of use plans, i.e., ways of manipulating objects in order to realise practical goals. Most of the chapter is devoted to presenting our analysis of using and designing. In section 2.1, we introduce our action-theoretical perspective, and in section 2.2, our central concept of use plans. Since this is just the start of a background story, we tell it by means of simple examples and provide no more than a basic analysis. In sections 2.3 and 2.4, we analyse using and designing in terms of plans: the former is cast as the execution of a use plan, and the