Abstract:Taxicabs are one of the least studied urban transportation systems. Taxis make more than 8% of the total motorized trips in Bogotá, Colombia (this figure is 4.3% in New York City, 2.2% in London, and 0.8% in Paris). Understanding the main differences in taxicab operations during the day and the night (involving drivers, vehicles, and service) will yield important conclusions that may help implement policies toward sustainability, help the industry improve efficiency, and contribute to understanding this mode of transportation. The objective of this paper is to explore the differences in all aspects of the supply of taxicabs in Bogotá between day and night. The analysis is based on 389 drivers' surveys in the city. Radio dispatch devices played an important role in night operation, more specifically for road and personal safety. In addition, drivers in Bogotá did not always seek to maximize their profit. With respect to sustainability, taxicab operations during the night was more efficient (less fuel, more income, and more resting time). This study aims to enrich the scant and limited literature on taxicabs, with the hope that it will motivate similar studies in other cities.