Since the first intravenous nutrition support attempt with olive oil in the 17th century, intravenous fat emulsions (IVFEs) have evolved to become an integral component in the management of patients receiving home parenteral nutrition (HPN). IVFEs serve as a calorie source and provide essential fatty acids (linoleic acid and α-linolenic acid) in patients unable to achieve adequate intake of these fatty acids through alternative means. However, IVFE use is also associated with multiple complications, including increased infection risk, liver disease, and systemic proinflammatory states. In the United States, most IVFEs are composed of 100% soybean oil; internationally multiple alternative IVFEs (using fish oil, olive oil, and long- and medium-chain triglycerides) are available or being developed. The hope is that these IVFEs will prevent, or decrease the risk of, some of the HPN-associated complications. The goal of this article is to review how IVFEs came into use, their composition and metabolism, options for IVFE delivery in HPN, benefits and risks of IVFE use, and strategies to minimize the risks associated with IVFE use in HPN patients.