Persistent challenges in the construction industry include wastage of materials, budget overruns, schedule delays, and low labour productivity, where it is reported that more than 30 percent of construction works are non-value adding activities. The purpose of this research is to examine the performance of two major lean construction practices, namely, 5S System and Last Planner System (LPS), in reducing wastage in construction sites and enhancing productivity for a residential-commercial building project in Ahmedabad, Gujarat. A mixed methodological design approach was employed in this study where a field study was carried out for 15 days and two questionnaires were administered among 82 construction professionals in various designations such as Project Manager, Planning Engineer, Site Engineer, Supervisor, and Contractor. The Relative Importance Index (RII) was used for analysing data collected through this study. The 5S System had an overall RII of 0.869, resulting in an approximate reduction of between 8–12% in material waste and between 10–18% increase in labour efficiency. The Last Planner System was more efficient with an overall RII of 0.890, leading to a reduction of between 12–20% in project delay and between 15–22% increase in productivity. The percent plan complete increased from 60% to 85% after the use of LPS. Some of the major challenges associated with lean implementation include lack of awareness, inadequate training, and lack of acceptance towards change.