Hi again, I'm trying to set up a workflow for Galaxy (6799:40f1816d6857), but I can't seem to find a way to make a workflow that invokes another workflow. It seems like this wouldn't be unreasonable, since workflows have defined inputs and outputs. There might be another way to accomplish what I'm trying to ultimately do, though. We have a set of analyses and conversions, and want to assemble a workflow that goes through a long series of steps. The workflow can roughly be organized into three parts. Once the workflow is finished, we might want to rerun the third or second and third parts after modifiying some of the intermediate files. It seems like this might also be accomplished by somehow marking that some input files should be substituted instead of using the outputs of some of the steps in the workflow. Anyway, I've been unable to find a simple way of doing this.. I could make each part of the workflow a tool, but if I also wanted to expose the tools used in each part, I would be duplicating those invocations and increasing the maintenance burden. I could also make separate workflows for parts 1+2+3, 2+3, and 3, but that would also be duplicating work and increasing the maintenance burden. I could also make this three completely separate workflows, but that would mean that the user would have to remember to run each of these separately. Each part can take a very long time, so it would be useful to have this set up so that a user can start from the first part on a Friday and have the output from the third part available on Monday. Thanks in advance for any help, ~Aaron