In this chapter, I will provide the theoretical grounding for the whole thesis, whose main aim is to reinterpret SSM from the “actuality” point of view. In everyday English, “actuality” is very close to “reality”; but in this thesis, as I explained in the Introduction, I use the words “reality” and “actuality” in the special sense used by the Japanese phenomenological psychiatrist Bin Kimura. Although this concept of “reality/actuality” could be regarded as being close to notions of objectivity/subjectivity, I avoid this kind of philosophical dispute. Instead, I build on actual case studies and Kimura’s extensive practical psychiatric experience in order to reinterpret Checkland’s SSM as action research, and to show the basic convergence between SSM and Kimura’s theory.