Fruit- and vegetable-derived (poly)phenols have long been lauded for their potential health benefits in humans. Given their ubiquity and diversity in the diet, fully understanding the mechanisms responsible for their health effects is challenging. In light of this, many investigators have sought to understand the absorption, distribution, metabolism, and excretion (ADME) of (poly)phenols, with many now attributing their health effects to the (poly)phenolic metabolites formed within the gastrointestinal tract itself. In addition, given the recognition of the gut microbiome as an important contributor to both (poly)phenol metabolism and overall health status, recent years have seen a flurry of research activity aimed at understanding the bidirectional relationship between bioactive (poly)phenols and the gut microbiota. The goal of this review is to provide practitioners with a rudimentary understanding of how (poly)phenols are processed throughout the body, with a focus on their gut microbial metabolism. Understanding (poly)phenol metabolism is key to identifying the phenolic metabolites in systemic circulation that are ultimately responsible for the health effects derived from these dietary bioactives.