## 2 Theoretical Framework  
### Equity in Urban Mobility  
Transport planning in cities must comply with not only the fair spatial distribution of infrastructure but also with actions that promote equitable services across the population of different socioeconomic characteristics [23]. Three main perspectives take into account equity in how urban mobility is established [23]:  
* Uneven distribution of travel resources;
* The inequalities implied in travel behaviors;
* Accessibility (differences in conditions of access to transport modes, infrastructure, and urban space). The benefits from the provision of equity in transport services are related to the increase in accessibility to destinations of interest and the improvement of opportunities for using transport services [24]. However, attention needs to be paid in order to minimize the direct environmental harms caused by the use of transport services, such as air pollution exposure, the degradation of infrastructure, and longer waiting times before interventions take place. Moreover, the benefits and burdens should be fairly distributed in society (distributive justice) through transport justice, which includes the fairness of processes and procedures of decision and distribution (procedural justice) [25]. According to the Guidelines and Roadmap for EU equity planning [26], the main equity goals that need to be achieved in cities are the fair allocation of transport resources, the provision of equal opportunities to enable people to be mobile and have access to important activities in their life, and the reduction of the adverse effects of the transport system, which includes pollution, accidents, and social exclusion. Figure 1 shows a diagram of elements that need to be considered for an equitable mobility planning policy. Regarding the implementation of fairness in cities and transport systems, the proposition and creation of Sustainable Urban Mobility Plans (SUMPS) should take into account the elements for equity planning, as well as to meet social equity issues [27]. Therefore, SUMPS should work as a strategic tool to ensure that all citizens are offered transport options that meet their needs and enable access to key destinations and services, improve the efficiency and cost-effectiveness of the transport of people and goods, and contribute to enhancing the attractiveness and quality of the urban environment and urban design for the benefits of citizens, the economy, and society as a whole [28]. The current transport planning for most cities around the world still prioritizes the car as a mode of transport for the majority of the displacements. However, reforms need to be created to promote a more equitable transport system that relies upon multimodality [29]. For this, equitable planning reforms in transport systems need to consider all the factors that affect accessibility, including multiple modes, network connectivity, land use factors  
Figure 1: Strategic elements for an equitable mobility planning policy. Source: [26]. such as density and mix, and user costs [30]. In addition, mobility plans that value equity need to consider all significant community goals, including cost-efficiency, affordability, public health and safety, economic opportunities, community livability, and environmental protection, as well as recognize the unique and important roles that non-auto modes play in reaching an efficient and equitable transport system [29]. Another means of improving transport equity has emerged in recent years, with the introduction of transport technologies that enable services of shared mobility (e.g., car sharing and micromobility sharing). This new addition to the transport system is seen as a way to reduce the equity gap within the current transport network; micromobility-sharing programs can be used to feed public transport in areas with reduced accessibility [31].