By the 1960s and 70s, the field began developing theories and conducting theory-based research because up until that point, the field had been rooted in trial-and-error intervention research.[2] This era also brought along the development of new training methods such as the use of computers, television, case studies, and role playing.[2][3] The scope of training and development also expanded to include cross-cultural training, focus on the development of the individual employee, and the use of new organization development literature to frame training programs.[3] The 1980s marked a shift to focus on how employees were receiving and implementing training programs, and encouraged the collection of data for evaluation purposes, particularly management training programs.[4] The development piece of training and development became increasingly popular in the 1980s and 90s, with employees more frequently being influenced by the concept of "lifelong learning".[5] It was in this decade that research revealing the impact and importance of fostering a training and development-positive culture (including management and co-worker) was first conducted.[5] The turn of the century brought more research in topics such as team-training, for example cross-training.[6] Cross-training emphasizes training in coworkers' responsibilities.[6]