One document library or multiple document libraries?

Question

I am using Sharepoint 2010 Enterprise. What is the best practice for creating document libraries? ie how many and where to put them?

I have standard business units which will exist as their own subsites, ie Human Resources, IT, Finance, Corporate etc. Each department has their own set of documents. Am I better off creating one document library with a column to filter by department type and put all the documents in there, or am I better off creating one document library in each subsite to store its respective documents?

I realise either way may be suitable but would like to know what the favored approach is (if any)?

Answer 1

Well, I would suggest the decision depends on factors like security, sensitivity of documents. If you would like to restrict the documents to each department, then it make sense to add them to respective sites. Also, if you are dealing with large number of documents per department, search and retrieval of documents would be much easier with document library on each sub-site for its members using managed-metadata or search.

Note: This is what I had followed, based on experience with my clients. Hope this helps.

Answer 2

Different departments implies different permissions. Even if this isn't the case, it's very possible that this is desired in the future. That's why I always go for separate document libraries in each subsite.

Of course, you could create an extra document library in the top site, for documents of global concern.