Digitalisation changes opportunities and infrastructures in all areas of life, but still cities are ahead of rural areas. Conversely, ageing, as part of the demographic change, is more ad-vanced in smaller towns and villages. The interaction results in a polarisation of urban and rural areas and combined with a large cohort of retiring baby boomers, disruptive develop-ments are taking place. The complexity creates uncertainty among the re-sponsible local actors and requires new methods and instruments in spatial planning. However, most municipal actors have so far made inadequate use of existing data and information as well as digital media. In addition, the needs, behaviour patterns and potentials of baby boomers (and other cohorts) are largely unknown.

We aim at discussing evidence-based, data- and AI-supported and participatory decision support systems (DSS)to support municipal stakeholders. With the socio-spatial approach, we ask for integrated planning for infrastructures, services, accessibility, capacities and the use of finances.

We are planning two sessions of 90 minutes each, covering two major areas of this topic: on the one hand, the socio-spatial, target group-specific and accessibility aspects, and on the other hand, the issues around data, availability and heterogeneity of data, (administrative) data processing, results, decision making, data protection and ethical use of data in urban planning.

Following questions may be addressed:

a) Socio-spatial and accessibility aspects

• Which offerings and services within the municipality/region are accepted by specific population groups and can be accessed in which analogue and/or virtual form?
• Which scenarios can be designed for a high quality of life for different population groups based on local data?
• Spatial transformation in urban, suburban and rural areas: Which social and cultural infrastructures are affected by digital change and ageing? What impact does this have on other areas?
• What would help local stakeholders to make better decisions for spatial future development?
• Which trends are crucial for future developments in the municipality? How can different fields of action be defined?
• What are the basic impacts of an ageing population on spatial patterns?

b) Decision Support Systems as tools in spatial planning

• How can existing (and highly likely heterogeneous) data from the municipalities be made accessible and usable?
• Can concrete solutions be found for e.g. the accessibility of leisure facilities, residential locations or mobility of baby boomers with the help of mathematics and AI?
• How can complex theoretical mathematical models be applied in such a way that socio-spatial questions can be answered in order to optimise decision-making processes?
• Which technologies can be used for data acquisition, processing and integration that ensure transparent sensitive data protection?
• How can municipal data be integrated and used in a public interest-oriented way while abiding the regulatory and legislative framework for decision support systems (DSS)?
• What are the content-related requirements for a DSS regarding its target audience and, in particular, baby boomers?
• How can aspects like ethics, transparency, and explainability be considered in the development of a DSS?

We invite researchers and practitioners to report on babyboomers, impacts of digitalisation and access of ageing populations, and discuss projects and experiences with municipal data processing, use of DSS, and examples to engage in an exchange about possibilities and limits of evidence-based decision-making and participation opportunities in cities and smaller municipalities.