The shortage of skilled labours and the successors in the construction industry poses previously a very large problem. However, the actual working conditions of skilled labours are not grasped correctly. Therefore, the radical remedy of this problem is not shown. In the research presented so far, authors have pointed out the actual condition that specialist-contractors have separated a large majority of skilled labours from the employment which is a premise of various social security systems in order to ease the burden of the labour expenses outside wages. Institutional complexity is not independent, either, although the first factor is in the labour cost which fell even to the limit in recent years. Variables which specify the relation between skilled labours and specialist-contractors, such as law and various practices, are manifold and complicated, and we have never come to describe particularly. This research investigates the skilled labour's working conditions, referring to exactly the legal welfare expenses, Labour Standard Law, Construction Business Act and Tax Regulations based on former survey experiences. Besides, new criterions of judgement about employment relationships, such as wearing the helmet, are added. These will show the realities of working conditions of skilled labours rationally and exactly.
