Gary Pisano, professor at Harvard Business School, studies innovation at companies large and small. He says there’s too much focus on the positive, fun side of innovative cultures and too little understanding of the difficult truths behind sustained innovation. From candid feedback, to strong leadership, to individual accountability and competence, to disciplined choices, Pisano says leaders need to understand and communicate these realities. He's the author of the HBR article “The Hard Truth About Innovative Cultures” and the new book “Creative Construction: The DNA of Sustained Innovation.”