Ecolab has gone from having a relatively affordable price-to-earnings ratio at the beginning of the year to being a far more expensive company today. The biggest reason has been the large acquisition of Nalco, which isn't being fully represented in Ecolab's earnings at the moment. Despite what looks like an expensive company on paper, Ecolab's underlying business is actually fairly priced for its growth, though it may never be fully reflected that way due to its growth-through-acquisitions approach.

For the long-term investor, Ecolab is a great investment today, but there may be some even better options, including the "3 Stocks That Will Help You Retire Rich." In our premium report, we reveal some stocks that could help you, as well as some winning wealth-building strategies. Click here to keep reading.