Professional instructors intuitively promote the principle of interaction as one of the keys to effective training for adults. Recent findings in neuroscience are generating new knowledge that can reinforce or adjust educational policy and practice. One key area of neuroscience research shows some types of adult learning benefit from and requires the interactions of others. Recent findings on brain function and collective intelligence are a rational factor to add to the list of why adults learn best through collective and interactive activities. Networking needs to be promoted as it stimulates our individual brains and collective intelligence. Group interaction is important in the learning curve. This article focuses on learning with others and is split into two parts: Why should we care about collective intelligence? And, how can we incorporate collective-intelligence learning into training programmes?