Tuckman published a theory generally known as "
Tuckman's stages of group development" in 1965, while he was based at the
Naval Medical Research Institute. According to this theory, there are four phases of group development, namely:
forming, storming, norming, and performing. In 1977, he and co-author Mary Ann Jensen added a fifth stage, adjourning. In 1991 Tuckman researched and developed a 32-item procrastination scale, which measured the degree to which a person procrastinated. Professor Tuckman was also an avid runner who wrote the novel
Long Road to Boston (1988). ==Bibliography==