The trials of coping with negative aspects of behaviour such as absenteeism, lateness, and labour turnover have persuaded many companies to abandon the assembly line mode of mass production. Job enlargement exercises have demonstrated the benefits of assigning the building of a complete unit to one operator, thereby eliminating the co-ordination problems associated with dependent stages, but unless accompanied by a radical reappraisal of methods this may lead to a large increase in standard assembly time per unit.