Diversification
Diversification1, while similar in concept to asset allocation, goes further in balancing risk and return. Asset allocation gives you some basic diversification by determining how much of your portfolio to invest in stocks, bonds, property etc. Deciding which specific stocks and bonds to invest in and by how much gives you further diversification.
The net result is if one of your investments isn’t tracking well, having a diversified portfolio potentially means the gains from your other investments may offset this. Diversification can be a way to seek to build an efficient investment portfolio that meets both your appetite for risk and return.