Answer: Participate in your 401(k) plan as soon as you are eligible. A recent survey by Hewitt Associates found that less than half of those in their 20's contribute to their 401(k) plan, while 40% of those who do participate don't contribute enough to receive their employer's full matching contribution.

The quality of your children's retirement will largely be determined by the amount of money they save, and a 401(k) plan is a great place for them to start. Before marriage, a new home, and other obligations consume their entire paycheck, get them into the habit of saving. Because the contributions are deducted before they even see their paycheck, it is a great way to get them into the habit of saving on a regular basis.

Having trouble convincing them this is a good strategy? Perhaps a few numbers will make the point. Assume your child starts contributing to his/her 401(k) plan at age 25, contributing $6,000 per year (substantially below the maximum contribution in 2007 of $15,500), with matching employer contributions of $3,000. If he/she earns 8% annually, he/she could have a balance of $2,331,509 at age 65, before the payment of any taxes. What if he/she waits until age 35 to start contributing? At age 65, the balance could be $1,019,549, still a substantial amount, but $1,311,960 lower than if he/she started at age 25. Contributions for the first 10 years make a substantial difference in the ending account balance. (This example is provided for illustrative purposes only and is not intended to project the performance of a specific investment vehicle.)

What if your child still isn't convinced? Consider reimbursing him/her, as part of your annual gift tax exclusion, for any 401(k) contributions. You can reimburse the entire amount or offer to make a partial reimbursement.

Don't let your child procrastinate because there are too many decisions to be made. Just encourage him/her to start contributing, reassuring him/her that none of the decisions are permanent. He/she can review contribution levels, investment choices, beneficiary designations, and other matters at a later date.

If your child has the option to contribute to a regular 401(k) plan or a Roth 410(k) plan, he/she should evaluate the Roth 401(k) plan carefully. Employer matching contributions will still be made to a regular 401(k) plan, but your child's contributions can go to the Roth 401(k). Your child won't get a current tax break for contributions made, but he/she will owe no taxes on the contributions or any earnings when withdrawals are taken. Generally, investors who are in a higher tax bracket at retirement relative to their current tax bracket while making contributions to a Roth 401(k) will benefit more than an investor who is in a lower tax bracket at retirement. There are several differences between a Roth 401(k) and a Roth IRA, so make sure your child understands the basics before he/she starts contributing. See What Are Roth 401(k) Plans? for additional information on the differences between Roth 401(k)s and Roth IRAs.

What if your child doesn't have a 401(k) plan at work? Encourage him/her to contribute to an individual retirement account (IRA). Although contributions are limited to $5,000 in 2008 compared to $15,500 for 401(k) plans, IRAs are still a good way to save for retirement. Again, suggest a Roth IRA rather than a traditional deductible IRA. While your child won't get a current-year tax deduction for contributions made, qualified withdrawals can be taken with no tax consequences.