The construction industry, owing to its nature, tends to be rooted in a position in which the products tend to differ from one site to another and hence frequently calling for flexible teams of workers having a broad range of skills and the industry tends to be relatively sensitive to type changes in wider economy. Construction is hence normally highly reliant on migrant workers since they are a mobile labour force which is also flexible besides being reliable, especially during economic downturns. The construction industry of New Zealand, as is case with any other construction industries in other countries offers an ideal illustration of the ever-changing nature of work and the effects that has had on occupational health and safety of sub-contracted migrant construction workers. The vulnerability of migrant workers in the construction industry of New Zealand is examined in this research to establish the various challenges that are experienced by this group and thereafter offers a discussion on ways forward regarding creation of a more effective regulatory regime and a safer and healthier industry besides. This study delves into some of challenges that face such attempts to have access to decent, fair, and safe working conditions within the construction sector and relates them to the similar challenges which occur in other sectors in New Zealand. Migrants have historically been a source of labour for various construction markets across the industrialised and industrialising nations alike. While acknowledging the significant variation in construction activities and construction labour markets, this study explores the differences in working conditions and employment relations for migrants deployed in construction and comes up with some of universal conditions and common challenges which are faced by migrants to New Zealand, some of which go beyond a single labour market. An assessment is made as to how this research can be the basis for further research and its findings applied to improve the existing labour legislation and policies.