An investment strategy in which one investor allows a second investor to control where and how to invest the capital. The sidecar investment will usually be used when one of the parties lacks the ability or confidence to invest for themselves. The strategy will place trust in someone else's ability to gain profits.

The word "sidecar" refers to a motorcycle sidecar; the person riding in the sidecar must place his or her trust in the driver's skills. This differs from coattail investing, where one investor mimics the moves of another.

For example, suppose there are two individuals - Fred, who is experienced in trading stock, and Barney, who has a background in real estate. They decide to work together in a sidecar investing strategy. In this case, Fred would give Barney money to invest in real estate on his behalf and Barney would give Fred money to invest in stocks. This setup allows both Fred and Barney to diversify their portfolios and benefit from one another's expertise.