Actually, you may want to consider investing in target date funds outside your 401(k) as well. If you like the idea of an all-in-one portfolio that does the rebalancing for you, target date funds are available in many retirement savings accounts, such as an IRA, a rollover IRA or a brokerage account. Also, unlike the target date fund in your 401(k) plan, an account outside your company may allow you to choose from a wide range of target date fund providers.