Despite the headlines and the excitement the UK vote is causing, investors should pay little attention. Avoid the temptation to tinker with your investments based on fear about 'what might happen' because of the UK vote. From an investor's standpoint, little will happen.
Portfolio drift is when the natural movements of the market cause your investments to stray from your strategic asset allocation. One asset class has done extremely well, causing it to be overweighted in your portfolio. When this happens, you need to manage the drift through rebalancing or you could leave yourself more at risk in a market downturn.