We have clearly defined areas of responsibility. Dev A is responsible for features A, F, and Q, Dev B for features B, M, and C, etc. There is no overlap. We have multiple EXEs and DLLs. In the product I work on, Data Entry, Scripting, Reporting, Import, Export, database access are all separate modules. If anyone has a problem with database access, one guy handles that, import/export is another guy, scripting is someone else, data entry still a different dev.

If you are getting lots of build problems, move to an environment of unit testing and continuous integration. You'll know quickly if something breaks...and who did it.

>Yeah, I didn't mean merge in the literal sense, more of just making manual changes when differences are known/discovered. How do you keep developers from walking over each other's stuff though? That's what I'm really after. More of a process. I understand about making changes across versions, but in the examples I asked about, there is all kinds of room for error and things getting missed. Multiple developers, multiple projects, production code, etc. Just seems like there should be a way to handle it all without having to call each other up and ask "So, hey, do you recall what files you changed for your project, because I'm getting errors, blah, blah, blah..."
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