A topic is a self-standing theme which can be addressed by a working session of an expert panel or a section of a Delphi questionnaire. A topic can be, for instance, a technological area (e.g. fuel cells) which is itself smaller than a sectoral issue (e.g. energy technologies).
Selecting the topics is a crucial part of the process. For each topic one perspective should be defined. The scope of the exercise can be seen as the ensemble of topics with the perspective which is associated.