Australian doctors are treated as NZ doctors with no barriers to employment. Other doctors should allow 3-9+ months to find a position and fulfil the requirements for working in NZ. You should also anticipate needing to work in a single hospital for at least 6 months (3 months for some specialists). Registration and visa requirements usually preclude overseas trained doctors from working for short stints or in multiple hospitals.
Registration requirements
Doctors trained in Australia are treated the same as NZ trained doctors and can easily get registration in New Zealand. This costs around $500 annually. For further information about registration in New Zealand please see the Medical Council of New Zealand website.
Doctors trained in the UK, USA and Canada can almost always get registration in NZ without sitting exams. Registration and visa requirements take from 3-9 months.
Doctors trained in other countries usually need to pass the NZREX clinical exam to gain registration in NZ. Before sitting this exam applicants must pass one of a number of written exams (USMLE, Plab, AMC). The NZREX can only be sat in NZ. It usually takes a minimum of one year to complete this exam. For further information please see the NZMC website.
Visa Requirements
Australian citizens do not require a visa to work in NZ. All other doctors will usually be granted a work visa once they have a job offer and registration to work. For further information please see the NZ Immigration website.
Indemnity
Doctors in NZ must hold their own indemnity cover. The cost of this will typically be refunded by the hospital where the doctor is working in just one hospital while in NZ (this is usually the case.