Message End/Start Event in sub-process

Hi Community,
Would appreciate if someone could please help me figure out issue with below bpmn flow.
I have a main (sub-process) which ends with an ‘Message End event’, and inside that main (sub-process) is an nested sub-process which basically listens to the end event triggered.

But , it looks like the nested-subprocess is not getting triggered , as I cannot find the user task getting created.

I just want to have a neat way of arranging subprocesses in my bpmn main sub-process and Start/End event seems fit to link the main-process and sub-processes.
(I guess I cannot use the link event to start the sub-process so I opted for message event)

Attached BPMN
check_wf.bpmn (5.9 KB)

Would really appreciate any suggestion.


Hi @jonathan.lukas ,
I know I have already open question in some thread (I am currently gathering more info it), appreciate having patience.
Also, hoping if you can help me figuring out what I am doing wrong with the attached bpmn.


Basic rule in BPMN design is that a message MUST cross a process boundary.
It is not valid to throw a message and receive it within the same process instance.

You seem to have over-simplified your example… Your sample would be best handled by using either subprocesses or Call Activities.
As a result of the over-simplification, I feel like I’m missing the root-cause for you wanting to use a throw message / Event Subprocess Message Start.

Hi @GotnOGuts ,
I am merely trying to simulate from the example provided in the camunda docs ‘Building flexibility into BPMN models | Camunda Platform 8 Docs’ .
I was just trying to arrange the event-based-sub-process inside the mail-sub-process and have it triggered from the main-sub-process and from the link above it seems it should be possible.
If I am correct, you are suggesting to use simple-sub-process and just connect it in the main process flow. But since I will have to use this sub-process in few other places in the same process so i will have to place in independent of the main workflow. Hope I am able to clear it?

That’s a slight misunderstanding.

The document you linked to is showing Event Based Message Start, but not responding to message from within the process, but accepting messages from outside the process. In the footnotes of the link, you can see that the message comes from the Order Manager, not from either of the messages being sent in the process.

If you are looking to have a process re-used a number of times, then Call Activity is your friend.

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Thanks @GotnOGuts . I just used call-activity to get the job-done.