Abstract: Despite the clear theoretical advantages of the activity-based model over the travel-based transportation demand model, its practical use in the transportation planning field has been slow. Based on the principle that transportation demand derives from activities, the activity-based transportation demand model has gradually evolved in the field of transportation planning over the past 40 years, with its focus mainly on academic applications rather than practical ones. This slow adoption is due to several factors, including its complex structure compared to the traditional four-stage travel-based model, the lack of standardization in modeling, conservatism among transportation planning practitioners or organizations, and limited technical resources. In the context of the Fourth Industrial Revolution, disruptive technological innovations such as autonomous driving, shared mobility, and urban air transportation are becoming increasingly prominent in the transportation field. Yet, tools for analyzing complex travel patterns still largely rely on existing methodologies. The rising demand for evidence-based decision-making and the advancement of data in both quantitative and qualitative aspects are prompting a reexamination of the activity-based transportation demand model. This presentation explores research trends and use cases of activity-based transportation demand models and proposes directions for future development.