I agree about equity exposure, low fees, and simple approaches like a three fund portfolio. Here is a slightly more sophisticated way to think about the percen

I agree about equity exposure, low fees, and simple approaches like a three fund portfolio. Here is a slightly more sophisticated way to think about the percentage that should be in equities. One year from now, equities could be up 25% or down 50%. Twenty years from now, equities are likely to be up, likely to have outpaced inflation, and likely to have outperformed "safer" alternatives (money market funds, bond funds, etc.). If you have a $10,000 bill coming due in one year, and $10,000 in the bank, it would be risky to invest any of it in equities. If you have money to invest that you won't be forced to liquidate for 20 years (e.g. your 401k at age 40), then it is probably fine to start with 100% of in equities. The percentage should be based on when you might be forced to liquidate each available investment dollar. In many cases this will agree with the rule of thumb. By equities I mean low cost equity ETFs (or index funds) that invest in broad indexes. I do not mean a portfolio of 10 to 30 stocks hand-picked by you or any fund manager. The hand-picked portfolio could be down 100% in 20 years, or in 1 year.