Network analysis method. History of Dependency Types.

Start-to-Start and Finish-to-Finish dependencies were not part of the original Critical Path Method (CPM) introduced in 1956 or Program Evaluation Review Technique (PERT) developed in 1957.

CPM and PERT were based on Finish-to-Start logic only.
It wasn’t until 1958 that Start-to-Start logic was introduced by French scientist Bernard Roy as part of the Method of Potentials. His work later inspired the development of the Hamburger Method of Networking (HMH technique) in Germany, which allowed the use of a Finish-to-Finish relationship.
These works were very much ignored, especially in the Unites States. The first complete description of Precedence Diagramming with five types of precedence relationships appeared only in 1964 in an IBM user’s manual.