Talking about documents and SharePoint falls under the category of ECM (or enterprise content management).
It can be an extremely tedious subject to discuss since it has a lot of unique terminology and some consultancies specialize in it. You can imagine if they start off talking about moving millions of documents from one system to another with a multiyear phased approach it can be a big deal. However you are in luck as we decided to bake the name "simple" into our company name many years ago with the premise that if you were truly expert at doing something you could do it in the simplest way possible. As SharePoint consultants and veterans for many files migrations we have some tips to make this as simple as possible.
In the following example we break down migrating documents from a simplistic ECM system (file shares) to SharePoint, however similar steps can be used when migrating from various other ECM systems to SharePoint.
Step One of course is to set up your local SharePoint to index so you can search all of your local resources.
File shares can be broken up into several areas with different search scopes. (clients / operations / marketing / everything)
Step Two is to review your current file shares and deduce a pattern.
Typically, files are organized with a combination of schemes that are mixed together. It's a little bit like looking at a messy closet and that if it was not your closet you might not get the pattern right off but whoever owns the closet has some degree of organization and they can find their socks from their shirts. With files, this consists of a combination of document purposes, dates, or related clients. So unless you are running your entire company out of dropbox there is already an organization within your file shares and that can be used. The process of reviewing it and producing a pattern from it is referred to by a fancy term that I love to use as it's Uber geeky. It's called "harvesting your intrinsic taxonomy." Meaning that it is organized in a way that is working for you now, and we can glean a pattern from it to start off a formal taxonomy that will service tags within SharePoint. What we typically do is have our clients run a batch file which will enumerate the folder names and file names. We then assist in coming up with a tagging taxonomy that everyone agrees make sense and is good enough for a start.
Step Three is to put the terms into SharePoint in its metadata storage or term store.
And then the magic occurs. We do a proof of concept with the most valuable files and typically we let our clients use Windows Explorer to drag-and-drop right into SharePoint folders that have been pre-tagged with your taxonomy terms. You then get the Amazon shopping cart like experience shown below.
Step Four is where everyone now understands the process and can speak the terminology of SharePoint ECM.
You then take a good look at what is important to migrate to SharePoint, and now that you know the work involved the resources can be planned and you can begin the process of migration of the rest of the body of files into SharePoint. Whether it's ad hoc, all at once, or some combination is entirely up to the client. We have many tools that can automate the process of migration. They can scan for illegal characters that cannot exist within file names and change these on-the-fly. They can apply metadata and tags to files as they are moved, and many other automation tasks.