Loot boxes are virtual items containing bonus content for video games. Their digital content is random and unknown to the player, which is why they are often compared to gambling. Over the past several decades, loot boxes have become increasingly common in modern video games and contribute to significant profits for the gaming industry. Unfortunately, research has illuminated the numerous harms associated with loot boxes, including, for example, financial loss and psychological distress. Moreover, there is evidence to suggest that loot boxes may act as a “gateway” to gambling. However, research is limited on whether or not there is a causal link between loot boxes and problem gambling, and additional research is needed to clarify the nature of the relationship. This chapter will provide an overview of the history of loot boxes and current popularity before discussing the shared characteristics with gambling. The link between loot boxes and problem gambling will be explored in-depth, including underlying mechanisms associated with negative consequences. Recent studies on loot boxes, including those that explore potential harms and risk factors associated with harm, will be examined. Finally, suggestions are made for future research, such as including objective data and diversifying samples. Clinical and policy implications will also be discussed.