Time-frames are defined by root events and therefore best defined along the same guideline, namely their scope and the nature of coupling.

Along that understanding, time-frames can be defined with regard to context (symbolic or actual) and coupling (asynchronous or synchronous):
- Symbolic, no coupling: time-frames set by internal events, involving a single actor.
- Symbolic, coupling: time-frames set by external events, involving a single actor.
- Actual, asynchronous: time-frames set by external events, involving different actors without real-time constraint.
- Actual, synchronous: time-frames set by external events, involving different actors with real-time constraint.
That taxonomy could be used to align time-frames with processes‘ execution mode.