The Securities Commission wants companies that issue securities to give investors more details about corporate governance including ethical standards, directors' pay and risk management.
The Commisssion says it recently reviewed the governance policies of 68 companies in annual reports and on their websites.
It found that many needed to improve their disclosure on six of nine corporate governance principles issued by the commission.
While many companies are good at revealing how much directors are paid, chairman Jane Diplock says they are not so good at telling investors how they came to that decision and how the pay aligns with the company's objectives and risk management policies.
Ms Diplock says companies could improve their reporting by complying with the commission's nine principles.
She says good corporate governance it critically important to the integrity and stability of any company, and the capital markets.