Portugal, Puerto Rico and Pakistan are just three of the 13 countries Hong Kong's first local ombudsman and his top staff visited last year.
Mr So revealed that the 14 trips, one of which involved nine staff, cost $500,000, or about two per cent of his organisation's budget.
Among his travels was a four-day visit to the National Commissioner for Human Rights in Mexico, followed by a week's gap, and then four days with the ombudsman in Puerto Rico.
He personally visited five countries.
Puerto Rico 'has a very long-established ombudsman', Mr So said.
'All my staff have worked in government departments or other institutions,' he said.
'To attain the kind of professionalism I have promised in my five-year plan I'm convinced it's my duty to try to bring them as many training opportunities as possible.' The full list of countries is: Portugal, Spain, Mexico, Puerto Rico, South Korea, China, Canada, Ireland, the United Kingdom, the Netherlands, Sweden, Pakistan and Macau.