The complexity of future societies will be reflected not only in the buildings that are created but also in the processes that evolve such buildings. Within the construction industry, and specifically in relation to large, complex multi-user buildings, operational planning and design processes will assume greater importance than ever before. Given that increasing complexity is likely to lead to increasing specialism and differentiation amongst the main contributing parties in a construction procurement project, it is also likely that there will be more disruption of the communication and organisation processes central to project procurement. These effects will be transmitted through the procurement process and manifest themselves in various ways in the final product. The most important of these will be the damaging effect which they will have on building function, where function determines the buildings' ability to serve as a facilitator of intended user group activities. Research has been undertaken to rationalise building design, operational planning and building function in the construction procurement process. Maintaining unity between the different parties responsible for building design and operational planning decisions is hypothesised as the key factor in evolving successful project procurement outcomes in terms of building function. Research into hospital food service building procurement processes has demonstrated that when building design and operational planning processes are not developed in concordance with one another, then deficiencies in the functioning of the food service system resulted. Seventeen design/operation mis-match outcome deficiencies were identified across three hospital construction projects. On further analysis of these project outcome deficiencies, it was apparent that the majority were due to problems that had arisen because design team members and user specialists had been unable to relate different aspects of system functioning adequately. In particular, there appeared to be an inability to incorporate effectively the catering technological and associated service aspects into the design solution, i.e. the elements that were not purely architectural. Some of these functional relationship problems were relatively simple and did not require significant design or user expertise. The most problematic deficiencies emerged when different components of the food service system (central production unit, distribution system and ward service) were not effectively integrated. Proposals are made for a planning framework which will maintain greater congruence between building design, operational planning and building function during the procurement process by allowing project contributors to assess the impact of different building design and operational planning decisions on the human/building interface. The planning framework focuses decision making around a set of critical relationships identified between the components of the building solution, so that any potential divergence caused by environmental pressures can be offset by corrective action using the critical relationships as the parameters upon which successful function must be based. This approach is a pre-requisite for the future construction procurement process in order to improve building function, particularly for complex, multi-user buildings.