By Cameron Huddleston, Former Online Editor October 14, 2009 Six of the world's great investors shared their outlooks and investment strategies with Kiplinger's Personal Finance for the November issue. Jeremy Grantham, chief investment strategist at Grantham, Mayo, Van Otterloo had this to say:The recent rally has been very speculative, favoring risky assets over the past few months. I'm sorry if you missed investing at the market's March lows, but don't compound the damage to your portfolio by chasing gains in risky assets. We're at the beginning of a seven-year period of lean returns. You should only be buying the highest-quality blue-chip companies, where valuations are most attractive.See 5 Blue Chips to Hold if the Rally Fizzles for our picks of safe stocks. And see Learn From the World's Great Investors for advice from five other luminaries.