Oh yeh!  Especially important for short term fluctuations.  We might even reccomend a collar on your portfolio ever now and again if we think the market is transitioning or correcting!  However, it most cases, a well diversified portfolio does it all.  However, focused investing says that you do not need to be diversified in the long term if you own the right companies, so you may see our portfolio turn un-diversified at points.