Don Tapscott: Always ahead of the trends, his new book, Blockchain Revolution, is the definitive guide for business people. 

Consultants & Educators

Business Agility Workshop: As part of my work helping companies decentralize, I help them understand blockchain and Ethereum.
B9 Labs: Education, seminars, training, coaching, and consulting by Ethereum natives
Chainsmiths: Training, custom development, advisory, based in Dublin
Daily Fintech: Bernard Lunn and company - Zurich & London. 
Nexus Squared: Blockchain entrepreneurs in Zurich.
Smart Contract Solutions*2: Custom smart contracts