Eric Ries is an American entrepreneur and author known for his work on startup methodology and entrepreneurial management. He wrote The Lean Startup, a book that became central to the lean startup movement, which emphasizes rapid iteration, validated learning, and customer feedback in building new ventures. Beyond The Lean Startup, Ries has also authored The Startup Way, which focuses on modern entrepreneurial management practices. Through his writing and work as a blogger, he has contributed significantly to how entrepreneurs and organizations approach building and scaling businesses.