The online survey began in November 2013, and has been carried out on a quarterly basis with the aim of canvassing a range of different-sized employers throughout New Zealand who were on the EEO Trust or the Chamber of Commerce Northern's databases.
NZ Work Research Institute director Tim Bentley, whose organisation analysed the research, said companies could do better by paying attention to areas such as the ageing workforce and flexibility.
Larger companies that claimed these matters were part of their culture should still have policies to make sure everyone was on the same page.
EEO Trust chief executive Bev Cassidy-Mackenzie said the most disappointing finding was that companies were still reluctant to employ older workers.
She believed this was because of a misconception that the ageing workforce would be slower, sicker and not as technologically minded as younger workers, and would find it harder to adapt.
Auckland Chamber of Commerce chief executive Michael Barnett said employers who did not address the ageing workforce were being short-sighted, as NZ had one of the highest older-worker participation rates in the OECD, at 20 per cent.
The survey also found employers were more aware of other workplace diversity issues.
More than 80 per cent of organisations had a formal policy on bullying and harassment.
Larger workplaces were also more likely than smaller ones to have policies and programmes, but only about 20 per cent of those surveyed measured their effectiveness.
The most common diversity practices were flexible arrangements so staff could work away from the main office at least one day a week, having female leaders and catering for disabled people.
Progressive Enterprises managing director Dave Chambers said his company's Countdown supermarket chain did not have a formal policy on ageing, but he believed it catered for a diverse workforce.
"What's important to me is that we work with our team as they progress in their careers and get older to make sure we're providing support and options for a future at Countdown."
Mr Chambers said 820 of the 18,000 staff at its 174 supermarkets and in distribution centres and support offices had worked for the company for more than 25 years.