This paper describes an interpretation of design activity through investigating design questions. From a number of previous studies two types of question have been identified: 1) reasoning questions; and 2) strategic questions. Strategic questions are part of an experienced designers approach to solving a design task. The paper describes how designers progress their tasks by asking questions at both reasoning and strategic levels. Transcripts of protocol analysis have been examined to identify both reasoning questions and strategic questions. These are discussed together with their relation to a problem solving model. The research aims to contribute to an understanding of design activity.