This chapter addresses the linkage of data sets, incorporating the characteristics of individuals using the technique of spatial microsimulation (SMSM). We present two case studies to exemplify how SMSM can be used in planning support systems (PSS), both of which are combining data from different sources. The first details ongoing work to produce household and population projections which are being used for resource planning for a range of utilities. The second describes a project estimating consumer demand for pork and other meat products in the UK. We offer some conclusions on the current challenges faced when linking data sets for the purposes of planning support and conclude that SMSM offers the potential to provide smarter, more flexible PSS because models are produced of individuals who require services and make decisions.