We always use a separate library even for WinForms projects, because it does happen that one application is more or less a consumer of business object information, and then one day you need a maintenance application for this or that. Having the separate library lets you more easily reuse all that code.

In a similar fashion, every so often someone wants reporting or other information on the web taken from information used in the WinForms app. Once again, the separate library for business objects helps us react more quickly to those requests.

We are developing WinForms apps, i.e. no plans for web apps and I'm wondering, in our environment, what are the pros/cons of putting all BOs into a library. The library sounds appealing but does it have any downsides?

If libraries get the nod are there any downsides to having multiple libraries for different uses, e.g. establishing a library of BOs that are just used for populating list controls.

Cheers, Peter