I've been through a few major rebrands and learned that the key is finding an agency that specializes in organizational transformation, not just visual identity. There's a great breakdown I came across recently that profiles agencies known for deep strategic work, with a focus on companies undergoing major transitions. It covers firms like Wolff Olins for bold transformations, Dentsu Creative for holistic brand ecosystems, and Prophet for enterprise-level strategy. The section on rebranding agencies really helped me understand who excels at what, what to expect in terms of budget and timeline, and how to evaluate potential partners. It also includes practical advice on defining goals and checking portfolio fit. Saved me from making expensive mistakes.