In finance and investing, rebalancing of investments (or constant mix) is a strategy of bringing a portfolio that has deviated away from one's target asset allocation back into line. This can be implemented by transferring assets, that is, selling investments of an asset class that is overweight and using the money to buy investments in a class that is underweight, but it also applies to adding or removing money from a portfolio, that is, putting new money into an underweight class, or making withdrawals from an overweight class.
Rebalancing of investment is a concave trading strategy; as opposed to constant proportion portfolio insurance (CPPI), which has convex payoff characteristic.