Effect of the Last Planner system® on social interactions among project participants

Construction is one of the oldest and most established project-based industries, bringing together a diverse collection of professionals for short periods of time. Within the temporary organization of projects, interaction among the participants ensures a smooth transmission of vital information that impacts the process of production planning. While involvement of participants in the planning process increases cohesiveness among them, the Last Planner System® (LPS) identifies detailed specification of the steps to be followed and the constraints to be removed for reliable execution of the project. To accomplish the goal of this study to understand the effect of LPS on the social interactions of the participants, a critical case study method was adopted. In-depth analyses of the interactions among the participants of two projects, one following LPS and another following traditional project planning, have been undertaken to illustrate the role of social interaction in each one of them. Weekly subcontractor coordination meeting was selected as the unit of analysis. Data has been collected using direct observation, and Interaction Process Analysis has been used to analyze the social interaction data. The findings provide a project-level understanding of the role of social interaction among project participants during LPS in comparison to that of traditional project planning. LPS increased the participants’ understanding and control of the work assignments, thereby creating a social system with more information and higher level of trust. Participants using the LPS exhibited more cooperation than those using traditional project planning, working within the social network of the project.