Especially in the last couple decades, training has become more trainee-focused, which allows those being trained more flexibility and active learning opportunities.[11] For example, these active learning techniques include exploratory/discovery learning,[12] error management training,[13] guided exploration,[14] and mastery training.[11] Typical projects in the field include executive and supervisory/management development, new-employee orientation, professional-skills training, technical/job training, customer-service training, sales-and-marketing training, and health-and-safety training. Training is particularly critical in high-reliability organizations, which rely on high safety standards in order to prevent catastrophic damage to employees, equipment, or the environment (e.g. nuclear power plants, operating rooms).[15]