This conclusion presents some closing thoughts on the concepts discussed in the preceding chapters of this book. The book focuses on the use of playfulness as a method of research, where adults and children were co-players in the data collection, again reflecting the power balance between the two. It describes how the first playworkers inhibited their adultness as a way of preventing the adulteration of children's perspectives. As with playwork practice, this subjective–objective interaction requires careful consideration when researching play, with the reflexive researcher acknowledging their own subjectivity–objectivity in the research process and employing both critical reflection and critical self-reflection. Playfulness within playwork practice appears to be 'mirrored' in playwork research. The play process often involves interaction between children and other people, which may sometimes involve playwork practitioners. Researching play is also both an objective and subjective matter, for both the researcher and the participants.