Senior doctors and dentists say they don't want to see anyone harmed by today's strike.
Members of the Association of Salaried Medical Specialists will strike for two hours from midday after rejecting Te Whatu Ora's latest offer.
Around 250 planned procedures are being changed as a result.
Executive Director Sarah Dalton says there are contingency plans.
She told Kate Hawkesby that she's been taking calls in the last few days about surgeries that can't be delayed, and they've approved staffing for that.
But Dalton says many procedures are currently postponed or cancelled across the country every day due to a lack of staffing.
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