It was originally called SOFT, before someone swapped Fault for Weakness.
The framework now taught in every business school began at the Stanford Research Institute in Menlo Park, California, where a research group called the Theory and Practice of Planning (TAPP) studied corporate planning practices from 1962 to 1971. The group was led by Robert Franklin Stewart and included Albert Humphrey, Melvin Branch, and others working with Fortune 500 companies.1
The original framework was called SOFT analysis. Humphrey later explained the categories: "What is good in the present is Satisfactory, good in the future is an Opportunity; bad in the present is a Fault, and bad in the future is a Threat."2 At some point between 1964 and 1974, "Fault" was replaced with "Weakness" and "Satisfactory" with "Strengths," producing the SWOT acronym. Humphrey did not identify who made the change.
Humphrey published his version of the framework in 1974 in a book titled Getting Management Commitment to Planning, where he introduced Participative Planning in a seventeen-step approach, beginning with identifying a firm's Strengths, Weaknesses, Opportunities, and Threats.3
A parallel lineage runs through Harvard Business School, where professors George Albert Smith Jr. and C. Roland Christensen are credited with using similar frameworks in the early 1950s, and Kenneth Andrews developed their application in the 1960s.4 A 2023 archival study by researchers at the University of Twente traced the SWOT pedigree through previously inaccessible SRI documents, confirming the TAPP group's role while noting that no single person or institution can claim sole authorship.5