The gmnl package in R helps estimate models that account for differences between individuals in their choices. These models can handle various types of individual differences, like continuous or discrete variations. The package supports different types of multinomial logit models, which are used to analyze choices made by individuals. Researchers can use this package to estimate these models using maximum likelihood or simulated likelihood methods. The package allows for estimating individual-specific parameters and measures related to willingness to pay using real-world data.