Kotter lays out eight steps for cultural change in this book. However, 17 years later, he shifted his perspective on organizational transformation from one that is implemented top-down to one that is based on voluntary bottom-up reforms.
Our Iceberg is Melting: Changing and Succeeding Under Any Conditions, a book by Kotter, is a quick read that explains why the "burning platform" is important for firms to transition to new ways of doing things