My 401(k) had some very expensive choices, and the best pick for me was the Black Rock S&P 500 index (BSPAX, expense ratio of .37). While I already had a fairly high amount in large cap stocks, all the rest of the choices had ERs that were MUCH higher, so that was the investment direction I took. But now, PIMCO has been dropped and the Vanguard Intermediate Term Bond Index Fund (Admiral Shares) has been added. I know my bond allocation is way lower than I want, and I definitely plan on having my future contributions go into VBILX with its nice low .10 ER. I also have the option now of transferring the BSPAX over to VBILX, which would get my overall allocations closer to what I want. But is now really the time to rebalance? The S&P has been down, so I would be "selling low" if I were to rebalance now. I am not trying to time the market or anything, but I also am not trying to make a dumb fund transfer just because it is now an option. I know when you rebalance you are supposed to sell the stuff that was up and buy the stuff that was down. But now the stuff I have too much of is down! So what do you think: transfer now, even though the S&P is down, or wait for a rebound?