I see mastermind groups working and let me tell you everyone that participates realizes a great value from it. The ideas that flow and new opportunities that come from that special moment when you say I knew that but never thought of it that way. Your business can grow greatly, in a short time, when these groups are formed. The downside is being part of a group that just wants to meet socially or you maybe not wanting to share certain aspects, (statements of confidentiality need to be signed), if the group is run to train the business owner, expand the thinking, hold the members accountable to accounting policies, other proven business principals and letting the group act like a board, the benefits are enormous.