The first structured method for documenting process flow, the [[flowchart| flow process chart]], was introduced by [[Frank Gilbreth]] to members of [[American Society of Mechanical Engineers]] (ASME) in 1921 as the presentation “Process Charts—First Steps in Finding the One Best Way”.<ref name="BBG02"> Ben B. Graham (2004). [http://www.detail-process-charting.com/chapter1.htm "Detail Process Charting: Speaking the Language of Process".] p.1</ref> Gilbreth's tools quickly found their way into [[industrial engineering]] curricula. In the early 1930s, an industrial engineer, Allan H. Mogensen began training business people in the use of some of the tools of industrial engineering at his Work Simplification Conferences in [[Lake Placid, New York|Lake Placid]], [[New York]]. A 1944 graduate of Mogensen's class, Art Spinanger, took the tools back to [[Procter and Gamble]] where he developed their Deliberate Methods Change Program. Another 1944 graduate, [[Benjamin S. Graham|Ben S. Graham]], Director of Formcraft Engineering at Standard Register Corporation, adapted the flow process chart to information processing with his development of the multi-flow process chart to displays multiple documents and their relationships. In 1947, ASME adopted a symbol set as the ASME Standard for Operation and Flow Process Charts, derived from Gilbreth's original work.<ref name="BBG02"/>
The modern FFBD was developed by [[TRW]] Incorporated, a defense-related business, in the 1950s.<ref>Tim Weilkiens (2008). ''Systems Engineering with SysML/UML: Modeling, Analysis, Design''. Page 287.</ref> In the 1960s it was exploited by [[NASA]] to visualize the time sequence of events in space systems and flight missions.<ref> [[Harold Chestnut]] (1967). ''Systems Engineering Methods''. Page 254.</ref> FFBDs became widely used in classical [[systems engineering]] to show the order of execution of system functions.<ref name="TD03"/>
