What makes public transit demand management programmes successful? A systematic review of ex-post evidence

Transit crowding results in negative experiences and mode change for transit riders and operational challenges for operators. The COVID-19 pandemic initiated an ongoing transformation of how, when, and where people travel, yet the challenge of balancing demand and supply in transportation remained topical. The pandemic has also exposed the traditional approach of infrastructure expansion for being too slow to respond to the challenges of crowding in a timely manner. As such, this paper provides a systematic literature review of the ex-post studies that evaluated the impact of transit demand management strategies. The paper synthesises the findings from 13 different programmes analysed in 20 studies. It is concluded that at least within the scope of the limited number of identified ex-post studies, the practice of alternative work schedules that allow employees greater freedom when to travel is the demand management approach that can bring the most significant crowding reduction. Once that flexibility is expanded, other strategies that appeal to riders’ preferences might have a larger effect as well. The findings of this review aim to encourage transit agencies to develop collaborations with large employers that can introduce alternative work schedules.