What is Brainstorming? Brainstorming is a creative method of generating a large volume of ideas free from criticism. Brainstorming was developed in the 1940s by an advertising executive who was frustrated with his employees. The employees were unable to individually develop ideas for advertising campaigns, but were successful during group sessions. Brainstorming is now one of the most well-known tools for developing ideas in business. Brainstorming as part of the DMAIC Pro