I knew there was some very dark and heavy energy at work after 3 people had died within a year, and that something needed to be done about it.
I felt the space clearing helped a great deal to lighten up the place - both a closure and a new beginning. I had tried several things to clear the energy myself (sprays, crystals, incense, etc), but as I was in the middle of it, I needed the help of someone without a connection to the place and situation.
My two closest colleagues also noticed the difference afterwards.
I would certainly recommend space clearing to help shift old energy be it in the work place or at home - it is so easy to get caught in habitual energy that does not serve anybody.