A NTUA Diploma Thesis titled “Investigation of the acceptance of reducing the speed limit to 30 km/h in all urban areas in Greece” was recently presented by Konstantina Gkoudinakou. For this purpose, a special questionnaire was developed that was answered by 302 drivers based on the method of declared preference for 10 hypothetical scenarios with variations in time, fuel consumption, and the probability of a road crash with casualties. Data were collected, processed, analyzed, and after many tests, a polynomial regression model and two binary regression models were developed to understand the factors that affect the acceptance of drivers in a city center to reduce speed limits. The results indicated the variables that significantly affect driver acceptance, such as increased travel time, reduced fuel consumption, reduced likelihood of road accidents with injury, driving frequency, the role of speed in causing accidents, the role of pedestrians in choosing driving speed, and certain demographic factors. This way, findings are also obtained regarding the social acceptance of the measure in relation to the characteristics of the participants, such as gender, age, education, driving behavior, and so on.