[10][11][12] Between August 1986 and September 1988, Ko served in the 269th mechanized infantry division of the Republic of China Army to fulfill his military service obligation.

After working in emergency services for 11 years, Ko traveled to the United States in 1993 for a one-year clinical fellowship program on artificial liver research at the University of Minnesota under Wei-Shou Hu.

On 15 July 2006, Ko wrote an article for the Min Sheng Daily titled "Reflections, Errors, and Apologies: Chao Chien-ming" that received considerable media attention and led to a number of politics-related interviews.

On 18 November, Ko used ECMO to save the life of Shirley Shaw, wife of Taichung Mayor Jason Hu, who had fallen into a coma after a car accident.

[21] In response to the political nature of the course and its timing, Ko explained that he enrolled because he had been asked to, and that he would not sign a petition requesting that Chen be pardoned for corruption charges.

[28][29][30] During a symposium in Kaohsiung, Ko revealed that the accusations of misconduct in the AIDS transplant incident were the main cause of his decision to run for Mayor.

[35][36] A number of "slips of the tongue" made it into the news, for example when Ko said that the "Lawyer Culture" of Taiwan should end, when he criticized Koo Lee-hsiung's Facebook posts grieving over the death of Chai Trong-rong as "too emotional", and when he possibly unintentionally revealed confidential patient information.

[44] On 10 November, Ko announced his intention to reject further monetary donations to his campaign, as the amount received by 31 October exceeded the NT$87 million cap set for Taipei mayoral elections.

DPP city councillor Chien Yue-yen, neurologist Pan Cheng-chih, and two recruits from youth outreach efforts were the acting spokespeople for the campaign.

[61] Ko embarked on an extensive urban renewal project in Taipei’s west end, directly translated as the Western Area Gateway Plan.

Comprising many interconnected projects, the plan aimed to create a more livable and family-friendly neighborhood with new options for parks and recreation, while highlighting the area’s history.

On the day of his inauguration on 25 December 2014, Ko ordered the demolition of a bus lane on Zhongxiao W road, as part of a larger traffic improvement project.

[71] The next stage of the project involved demolishing two bus terminals on the west side of Taipei Main Station and repurposing the space for a park.

[67] The expanded urban green space, renamed Taipei Travel Plaza [zh], encompasses over 5,000 square meters of grass.

[75][76] A previous administration had originally scheduled the lead pipes to be replaced by 2025,[75][77] but Ko accelerated the timeline when Hong Kong's 2015 drinking water scandal raised similar concerns about health effects in Taiwan.

[89] A third-party candidate, Ko represented a break from the traditional two-party system, and positioned his campaign as a force for real change.

[93] He was open to improving ties with China through cultural exchanges and economic cooperation,[94] while pledging to increase defense spending from 2.5% to 3% of gross domestic product.

[95] However, Ko was unable to come to an agreement with the KMT leadership, and on 19 November he publicly affirmed that he still intended to run as the presidential candidate of the TPP.

[98] Ko conceded the presidential election to Lai Ching-te, stating that the TPP had shown that Taiwan was no longer dominated by the Pan-Blue or Pan-Green coalitions.

[99] On 14 August 2024, Taipei prosecutors searched the office of a public relations firm which sells merchandise bearing Ko's "KP" logo, following allegations of false reporting of political expenses for the 2024 presidential election.

[101] After conducting a preliminary internal audit, a TPP spokesperson said that the discrepancy was traced to the accountant incorrectly merging expense items among different vendors, without informing anyone at campaign headquarters.

[102] The spokesperson further stated that the TPP had receipts to account for all previously unreported vendors, that each expense had been legitimately used on the campaign, and that no money had been personally pocketed.

[107] Ko accused the government of attempting to "suppress" opponents and lambasted the legal system and press for doing the bidding of President Lai Ching-te's Democratic Progressive Party.

[113] On 11 January 2025, tens of thousands of people attended a rally in Taipei to protest against a politicized judiciary and "political persecution" by the DPP.

Starting from his term as Taipei mayor, Ko has used the line "two sides of the Strait, one family" (Chinese: 兩岸一家親) to show his views about the relations with the mainland.

Ko confirmed that he legally used a portion of his presidential election subsidy, estimated to total NT$110 million, to purchase the office.

[128] In response, Gutmann's lawyer Clive Ansley stated:[130][131] ... No English-speaking reader to date has understood for one moment that Dr. Ko was acting as an "organ broker".

... We believe that language, translation, and the heated environment of the political campaign for the mayoral race in Taipei may be playing a role in misconstruing the author's intentions and clouding the issue.

Mr. Gutmann believes, and we think his book demonstrates, that Dr. Ko has acted honourably ... and that he has contributed significantly to the international effort to expose the medical crimes which continue to be perpetrated in China.Ko's wife, Chen Pei-chi [zh], was born in Penghu, Taiwan.

[citation needed] She is the director of Pediatrics for Taipei City Hospital, Heping Fuyou Women and Children's Health Branch.