When talking about investing, one could often hear the terms "active investing" and "passive investing". Usually, active means selecting investments and making decisions along the way, while passive generally means buying broad market indices and leaving them alone most of the time. Picture generated by ChatGPT However, one may look a little deeper than that. Assuming asset allocation remains constant, portfolio management can be looked at from two angles: Selection: “What do I buy?” Management: “What do I do with what I have vested?” Putting these two together, there would be four outcomes as detailed below. Passive–Passive Passive selection + passive management. The investor buys broad-based index funds or exchange traded funds (ETFs) and largely leaves them alone. There is little security selection and little portfolio intervention. Rebalancing, if carried out, is periodic and systematic, perhaps once or twice a year. This is probably the closest to what is commonly called a "set-and-forget" portfolio....