Even if you are working with electronic documents, in some organisations there will be a requirement to officially sign documents. Often this means that documents get printed, signed and then physically stored. Depending on your needs this may be perfectly acceptable. If this is not acceptable, for example due to storage limitations or a highly geographically distributed workforce, you will need to consider a way to formally capture electronic signatures.
This nice video shows how an electronic signature can be used to fulfil your business requirements with respect to record the act of signing a document. This can be done both internally as well with external parties.
An interesting aspect in this video is the possibility to emulate the physical practice to put a special “sign here” post-it within the document. I am not sure this is really what I would want in my organisation, however I am sure this could help improving user adoption in some organisations.
Please note: whether the electronic signature is legally acceptable depends on your jurisdiction and you should check your countries procedural and systems requirements.