Accessibility is a well-established concept in planning research. It measures the ease of reaching destinations or activities, or the potential for interaction (Hansen, 1959). In very general terms, accessibility can be defined as the level of ability to successfully reach a certain object, place, event, or person. It is a key concept for understanding the social and economic life of cities in particular and societies in general.
The purpose of this paper is to inform the ‘accessibility approach’ to transport policy, planning, and investment by means of critically analysing its implementation barriers in professional circles and how to overcome them. We argue that it is necessary to focus less on technological issues such as what are the best instruments and decision-making tools to promote the accessibility approach. There is now sufficient knowledge about that (Papa et al. 2016). Now, the priority is to identify the institutional, organisational and cultural barriers to this approach.
Mobility and transport networks can facilitate accessibility, but only to a certain extent. Defining accessibility as what is granted by mobility is a reductionism. In our view, mobility is in many cases a necessary condition for accessibility, but rarely is a sufficient one. Traditional transport planning has in numerous instances failed to realise this important nuance. As a result, traditional transport planning has frequently equated implementing measures aimed at increasing mobility to improvements in accessibility levels. That is not necessarily a very accurate way of understanding what happens. This is fully acknowledged by the accessibility planning approach. In fact, accessibility planning recognises that the absolute opposite to that might be closer to the truth: increasing mobility might represent less accessibility (Ferreira and Batey, 2007).
Conflicts between accessibility planning and the dominant transport planning culture have been a barrier to effective implementation of accessibility planning (Bertolini et al. 2005; Bertolini, 2012). This approach of ‘mobility-first’ planning and investment has largely failed to deliver on the broader urban goals relating to economic growth, social integration, and sustainable development. Conversely, implementing accessibility-based performance measures can allow regions to pursue more coordinated objectives around economic opportunity, social equity, well-being, and health.
Several reasons should encourage the application of the accessibility planning approach., as the potential benefits of using the accessibility approach in applied planning practice are massive. Among other benefits, it facilitates understanding with much greater accuracy how different social groups are served in different ways by the transport system and by public and private services. It also facilitates identifying with higher precision what prevents people from reaching certain places and develop or maintain certain connections. This happens because it offers valuable insights on matters as diverse as mobility and transport, time budgets and schedules, nature and quality of services, financial and economic constraints, just to mention some possibilities. For further insights see, for example, Ferreira and Batey (2007).
Another reason is that the accessibility approach has the potential of bringing diverse activity sectors (e.g. transport and land use, economics and health care, education and logistics) together to agree on shared actions. This happens because the accessibility approach makes evident the interconnections between individual preferences and characteristics, geodemographic properties, nature and quality of services available, and mobility issues such as travel time savings, travel costs, and levels of service experienced in the transport network. This is not the case with the traditional transport planning approach as its focus is narrower and essentially concerned with mobility issues.
A benefit is also that the accessibility approach has the potential to create a common language among different stakeholders for discussing community conditions and priorities. In this way this approach offers a particularly constructive framework for action on agendas shared by transport authorities, citizens, service providers, technical experts, and land owners. It is also very constructive for creating communication bridges among people with different academic and technical backgrounds. This happens because its epistemological underpinnings are strongly linked with social inclusion theory and its theoretical basis is not mathematics, economics or engineering (which tend to be quite exclusive disciplinary areas), but social science in general and planning in particular.
Finally, another advantage is that the accessibility approach is abundantly equipped with appealing visualisation tools and techniques capable of depicting information in very clear ways. It can therefore facilitate decision-making processes by means of providing powerful visual inputs that integrate and give answers to a wide range of questions and policy issues.
However, a number of barriers exist to making the use of the accessibility approach mainstream. As a result, mobility-oriented planning continues to dominate the professional world. In this paper we aim at uncovering the barriers that planners face when trying to apply the accessibility approach in planning practice and on the pathways to overcome these barriers. This research aim is relevant and timely. Indeed, in the existing literature the main focus has been on the technical properties of accessibility measures and tools, with some exceptions (Curtis & Low, 2012; Geurs & Halden, 2015; Halden, 2014). We believe that accessibility planning research needs now to move on to study in greater detail the institutional barriers that prevent the implementation of the accessibility approach. There are strong reasons to believe that stakeholders involved in planning processes are prone to perceive the accessibility planning approach as something with massive potential, but only when this is introduced in the right institution, adopting the best approach, with the appropriate strategic support, for the appropriate goals, with the correct indicators and datasets, and with the correct timing.
The paper is structured as follows. Following this introduction, section 2 provides a brief description of the methodology used. Section 3 reports the results of the expert’s survey, discussing the barriers to the implementation of the accessibility approach in planning practice and discusses pathways to mainstream accessibility planning. Some concluding remarks are drawn in section 4.