Lets say i have the following departments:
How to structure the documents from these departments in sharepoint (best practice - each department has different kind of documents/metadata)?
One group site with multiple document libary. One libary for each department.
One group site where only the built in document libary is used. The different departments are seperated with metadata/view.
One group site for each department.
Regards
It all depends on what value you are feeding. if it is just documents its always better to have one site with different document library for each department. Each library can have unique permission for different sets of users. Also if you want it more compact you can have just one library under a single site and have different folders inside the library for each department.
If you have different forms or different data defined for each department like users details or any particular announcement which you would like to display for a department, it is advisable to go for a different site for the department as it will create less confusion among users.
Its all about scalibility and maintaining it the way it looks user friendly, SharePoint has provided the feature, its up to you how you find it better.
This is quite a complex topic really and a tailor-made approach would be needed, depending on the size of your organisation and the number of users. As Ankit mentions it needs to be scalable, so you would need to anticipate how much documents will grow. Here is a link for some reading on Document Management. It's really a good blog, check out the categories that interest you as I have the feeling you would benefit from reading up before starting.
One point I would like to mention relates to architecture (design of your Sharepoint deployment). As your Sharepoint system becomes more developed you might want to link up and reuse some of your document metadata (fields) or list data. This is done with 'lookup' fields, which reuse/borrow information from an existing document library or list. If your data is scattered between many different Site Collections (i.e. Departmental sites) it is more difficult to interlink data. The SP Maven blog is a great source of information and includes posts on Information Architecture.
Sharepoint is really a big topic and there are many different ways of doing things - like navigation for instance and using meta-data (Term Store Management).
