As an education provider, you are also a New Zealand business and may hire foreign workers to work at your institutes.
Any worker who is not a New Zealand citizen, resident or permanent resident is required to hold an appropriate temporary visa granting them work rights to legally work for a business. If you are recruiting non-New Zealand staff to work at your institutes, you must be aware of immigration rules that apply to you as an employer.
Your obligations as an employer of migrant staff are very different to those as an education provider to international students.