Dependency

A dependency in project management is a link among project's terminal elements.

There are four kinds of dependencies with respect to ordering terminal elements (in order of decreasing frequency of use):

• Finish to start (FS)
• Finish to finish (FF)
• Start to finish (SF)
• Start to start (SS).

There are three kinds of depencies with respect to the reason for the existence of dependency:

• causal (logical)

It is impossible to edit a text before it is wrtitten

It is illogical to pour concrete before you dig the foundations

• resource constraints

It is logically possible to paint four walls in a room simultaneously but there is only one painter

• discretionary.

Traditional critical path-derived schedules are based only on causal (logical) dependencies. The critical chain method necessitates taking into account resource constaint-derived dependencies as well.

See also: project planning