The construction industry plays a major role in infrastructure development and economic growth; however, it faces several challenges such as material wastage, project delays, cost overruns, inefficient resource utilization, and environmental degradation. Lean Construction and Green Construction have emerged as effective approaches to improve productivity, sustainability, and overall project performance.

This research examines the role of construction managers in implementing lean and green construction practices in building projects. The study focuses on lean tools such as Last Planner System (LPS), Just-In-Time (JIT), 5S, Value Stream Mapping (VSM), and visual management, along with green construction practices including sustainable materials, waste management, energy efficiency, and resource conservation.

The research methodology includes literature review, comparative case study analysis, site observations, and questionnaire survey analysis. Two projects were studied to understand the impact of proactive construction management in lean-green implementation. Findings indicate that projects with active construction management involvement achieved improved workflow continuity, reduced material wastage, better coordination, enhanced sustainability performance, and improved productivity.

The study concludes that construction managers play a crucial role in integrating lean and green practices through effective planning, coordination, monitoring, resource management, and stakeholder communication. The research also identifies major barriers such as lack of awareness, inadequate training, resistance to change, and higher initial investment costs.

Keywords: Lean Construction, Green Construction, Sustainable Construction, Construction Management, Waste Reduction, Resource Optimization.