手法を比較

	ソフトシステム方法論（SSM）	Delphi Method	戦略的選択アプローチ
分野	問題構造化	質的手法	問題構造化
系統	Process / pipeline	Process / pipeline	Process / pipeline
提唱年	1981	1963	2005
提唱者	Peter Checkland	Norman Dalkey & Olaf Helmer (RAND Corporation)	John Friend & Allen Hickling
種類	Interpretive problem-structuring methodology	Structured iterative expert-elicitation process	Iterative group-based problem structuring and decision process
原典	Checkland, P. (1981). Systems Thinking, Systems Practice. Wiley. ISBN: 978-0-471-27911-2	Dalkey, N. & Helmer, O. (1963). An Experimental Application of the Delphi Method to the Use of Experts. Management Science, 9(3), 458-467.	Friend, J., & Hickling, A. (2005). Planning Under Pressure: The Strategic Choice Approach (3rd ed.). Elsevier. ISBN: 978-0-7506-6373-2
別名	SSM, Checkland's SSM, Soft Systems Analysis, Yumuşak Sistemler Metodolojisi	Delphi Yöntemi, Delphi technique, expert consensus method	SCA, Planning Under Pressure, Stratejik Seçim Yaklaşımı, Interactive Strategic Planning
関連	3	5	2
概要	Soft Systems Methodology (SSM) is an interpretive, action-research approach for structuring and managing complex, ill-defined ('soft') problem situations involving human activity. Developed by Peter Checkland at Lancaster University throughout the 1970s and formally presented in 1981, SSM guides practitioners through iterative cycles of inquiry that move from an unstructured problem situation to purposeful action through structured learning rather than optimization.	The Delphi method is a structured, iterative survey technique developed by Norman Dalkey and Olaf Helmer at the RAND Corporation in 1963 for eliciting and converging expert opinion on complex topics where empirical data are unavailable or insufficient. It collects independent judgements from a geographically dispersed expert panel over multiple anonymous rounds, feeding aggregated results back to participants after each round so they can revise their views in light of the group's collective position.	The Strategic Choice Approach (SCA) is an interactive, workshop-based problem structuring method developed by John Friend and Allen Hickling, first published in 1987 and refined in the definitive third edition of Planning Under Pressure (2005). SCA helps groups of planners and stakeholders manage interconnected decisions under uncertainty by explicitly mapping decision areas, option combinations, and sources of uncertainty before committing to action.