Abstract: Software engineering is rapidly evolving field with new methodologies, technologies, design tools, and paradigms emerging every year. Software industry is a relatively young business, actively searching for innovative ways of developing products. The latest trends towards a more customer-centric, responsive, iterative software development are bringing up new paradigms, frameworks in the field of software development processes. Lean software development is a translation of Lean manufacturing and Lean IT principles and practices to the software development domain which introduces a Continuous Improvement Model that provides a stable development model for organizations. Lean has become a standard for efficiency in production systems. This paper mainly focused on lean, principles and practices of Lean with Agile, importance of lean in reducing wastes during software development and maintenance.

Keywords: Lean, Lean Thinking, Software Development life cycle, Lean Software Development[LSD], Process Improvement,defects, Software wastes,Software maintenance.