Opus International Consultants says debt-laden central and local authorities will constrain infrastructure projects in its main markets for a number of years.
The Wellington-based firm's half-year profit has dropped to $10.8 million in the six months to June, down 5% compared to the same period a year ago.
The company says the decline reflects the fact that last year it got a $1.4 million tax credit.
Revenue rose 3.5% to $204 million.
New Zealand makes up threequarters of Opus's revenue, and chief executive David Prentice says a stronger performance in Christchurch has offset weaker results in other parts of the country.
Dr Prentice says the infrastructure consultancy market remains patchy in Australia too, where the company''s result has been tarnished by a bad debt of $600,000.
Sales fell slightly in Britain, though it recently won a seven-year road maintenance contract there.
Dr Prentice says the focus is on asset management in the UK, where the opportunities are growing.
He says the company continues to assess opportunities in other regions like the Middle East, North Africa and Asia.
Opus declared a half-year dividend of 4c a share.