Several studies have found fundamental flaws in the traditional approach to managing individual investors’ portfolios, including a failure to distinguish between $1 of pretax funds in a 401(k) and $1 of after-tax funds in either a taxable account or Roth IRA. This study recommends that an individual’s asset values be converted to after-tax values and the asset allocation be based on the after-tax values. In general, within the target asset allocation, individuals should hold bonds and other assets subject to ordinary income tax rates in retirement accounts and hold stocks, especially passively managed stocks, in taxable accounts.