Arborists gain qualifications to practice arboriculture in a variety of ways and some arborists are more qualified than others. Experience working safely and effectively in and around trees is essential. Arborists tend to specialise in one or more disciplines of arboriculture, such as diagnosis and treatment, climbing and pruning, cabling, utility arboriculture, or consultation and report writing. All these disciplines are related and some arborists are very well experienced in all areas of tree work, but not all arborists have the training or experience to properly practice every discipline.

Many arborists choose to pursue formal formal qualifications and/or certification, which is available in several forms in New Zealand.

An arborist can gain qualifications from Levels 1 through 4 in National Certificate or the Level 5 Diploma. Most or all of these qualifications are offered by several training organisations.

NZ Arb provides the Approved Contractor Scheme (ACS) for arboricultural contractors, which (among many other requirements) requires contractors to have an arborist with a minimum of Level 4 National Certificate. The Association is currently developing a similar scheme for Consultancies.

A Certified Arborist (CA) is a professional who has over three years of documented and verified experience and has passed a rigorous written test from the International Society of Arboriculture. Other designations include Municipal Specialist, Utility Specialist and Board Certified Master Arborist (BCMA). An arborist who holds certification in one or more disciplines may be expected to participate in rigorous continuing education requirements to ensure continuous improvement of skills and techniques.

The Tree Risk Assessment Qualified credential (TRAQ) designed by the International Society of Arboriculture was launched in 2013. At that time people holding the TRACE credential (introduced in 2005) were transferred over to the TRAQ credential. NZ Arb now offers regular courses in TRAQ.
Encouraging, fostering, improving and educating in all aspects of arboriculture throughout New Zealand.