Simply put, being a contrarian revolves around essentially trading against the trend... in other words, you're frequently doing the exact opposite of what pretty much everyone else is doing as a contrarian trader. Is it a good idea? Well... it can be :) For example, when the market has been what one could arguably define as irrational for a very long period of time, a good contrarian investor might decide that taking on a contrarian trade has a risk to reward ratio that is asymmetrically in his or her favor. However, do keep in mind that contrarian investing can be a dangerous endeavor as well. As explained in this video, any contrarian trader worth his salt knows that the market can remain irrational longer than he or she can stay solvent. In other words, one of the main risks associated with contrarian investors is being too early to the party. Or, to put it differently, if you jump on a trend reversal trade too early, you can lose money despite being "right" because by the time the trend catches up, you will have lost most of your capital on failed contrarian trends. In a nutshell, it's all a matter of having as many tools in your arsenal as your possible and being a good contrarian investor when the right conditions present themselves is most definitely a desirable skill to have.