Portfolio management is the art and science of making decisions about investment mix and policy, matching investments to objectives, asset allocation for individuals and institutions, and balancing risk against performance. It is the process of constructing a portfolio of assets that meets investors’ expectations and goals. It involves the selection of appropriate assets and their subsequent placement in the portfolio, determining the best mix and allocation of assets for maximum return and minimizing risk.

Portfolio management involves making decisions about which stocks, bonds or mutual funds to invest in and how much of each asset to purchase. The goal of portfolio management is to match investments to an investor's financial objectives, risk tolerances, and liquidity needs. Investment objectives typically include maximizing long-term returns, hedging against inflation, building liquidity, and reducing volatility of returns.

The primary objective of portfolio management is to maximize returns while managing risk. This is done through asset allocation. Asset allocation is the process of dividing an investment portfolio among different asset classes, including stocks, bonds, and cash, in an effort to optimize returns while minimizing risk. Successful portfolio management includes rebalancing the portfolio periodically to take into account changing market conditions, life circumstances, and investor risk tolerance.

When constructing a portfolio, it is important to consider the investor’s goals, the rate of return expected, the expected volatility of returns, the liquidity of investments, tax implications, and the timeline for reaching desired goals. It is also important to consider the diversity of investments, diversifying among asset classes, industries, and countries for greater stability. Investment costs and expenses, such as taxes and management fees, should also be taken into account.

Portfolio management can be done in two ways: actively and passively. Active portfolio management involves a manager making decisions about which stocks and other investments to buy and sell, as well as when to make such transactions in order to achieve better returns than a general index or benchmark. Passive portfolio management simply involves mimicking the makeup of an index, such as the S&P 500, or a combination of indices.

Portfolio management is a critical component of successful investing. It involves balancing the goals of the investor with the risk and return objectives. Achieving the best possible returns while managing risk is the primary objective of every portfolio manager. It is important to assess an investor’s risk tolerance and financial goals, select appropriate investments, and make strategic decisions about how to allocate investments in order to create a balanced portfolio that meets the investor’s requirements.