Nancy,
Perhaps I'm missing something obvious, but why don't you have app1 call app2, then app2 calls app3. That way it would be clear what App2's status was when you called App3. As long as you are working on a clear 'tree' system, with no branches linking, this should work.

HTH
Barbara

>We are developing a fairly large system that uses about 15 apps. The top level app selectively calls a sequence of lower level apps. A subsequent app cannot be called prior to the preceding app. I am looking for ideas to effectively have each app behave as if it were modal. We need to get the status back from app A prior to executing app B.
>
>One thought is to have each app set its status in a property of the top level app and then fire an event in the top level app to notify it to continue. One concern here is what would happen if the lower level app did not complete properly - but I can find ways of handling that.
>
>If you have dealt with anything similar before, I would be interested in hearing your ideas.
>
>Thanks much,
>Nancy