This paper investigates the relationship between headquarter work and full-time or part-time onsite workers by using the "skill biased technical change" methodology. From the middle of the 1990s in Japan, the number of full-time onsite workers and workers engaged in tasks at headquarters have been decreasing while the number of part-time onsite workers have been increasing. It was also confirmed that the role of headquarters changed from administrative tasks to entrepreneurial tasks over time.
From the estimation of a limited sample which covers only single-establishment firms, we disclose that the scale of headquarters decreases the demand of full-time onsite workers. Particularly, administrative headquarters have more influence on substitution with full-time onsite workers than entrepreneurial headquarters. On the other hand, the role composition of headquarters have various effects on skill biased technical change in each industry.