For calls and in-person talks where things might turn sour, start recording right away: you can record conversations you personally take part in without needing prior consent from the other party

There’s no cost involved. Simply turn on the call recording feature on your phone or use a recording app. Record the entire conversation, then keep the original file untouched — do not edit or overwrite it.

Article 66 of the Civil Procedure Law includes audiovisual materials and electronic data as evidence. Article 106 of the Judicial Interpretation of the Civil Procedure Law by the Supreme People's Court only excludes evidence obtained through three specific methods. These three are: those that seriously infringe upon the legitimate rights and interests of others, those that violate the prohibitive provisions of the law, and those that seriously violate public order and good morals. "Not informing the other party in advance" is not among these three. Article 15 of the Evidence Provisions of the Supreme People's Court: when using audio or video recordings as evidence, the original carrier, such as the original mobile phone, on which they are stored must be submitted. Article 90: audiovisual materials and electronic data containing doubts cannot be used alone to determine facts. A judge's article reprinted on the official website of the Supreme People's Court states the same: recordings must be obtained legally, the content must be authentic, there must be no editing, and they must be relevant to the case (National scope).

全国人大常委会 (2023 年修正，2024 年 1 月 1 日施行). 民事诉讼法（第六十六条）. 上海市发展和改革委员会转载全文 https://fgw.sh.gov.cn/ys-syjf-zc-2.4.1-h5/20240408/073febdb2b04464390546232d4089f51.html；最高人民法院 (2022 年第二次修正). 关于适用《中华人民共和国民事诉讼法》的解释（第一百零六条）. https://www.court.gov.cn/fabu/xiangqing/353651.html；最高人民法院 (2019 年修正). 关于民事诉讼证据的若干规定（第十四、十五、九十条）. https://www.court.gov.cn/zixun/xiangqing/212721.html；刘丹妮 (2023). 电影《消失的她》中的法律（人民法院报，最高人民法院官网转载）. https://www.court.gov.cn/zixun/xiangqing/406032.html

The beneficiaries are yourself and your family. In recordings, try to ensure that people, matters, amounts of money, and times correspond. Instead of just asking "When will you give it to me?", you can naturally ask "Regarding the 50,000 yuan I lent you last year, when do you plan to repay it?". Submit recordings to the court, arbitration commission, or police; do not post them online. Publicizing others' words may lead to privacy and reputation disputes; see item 16 of this section (Do not insult or spread rumors online). Having a recording does not mean you will certainly win; the court will also need to combine it with other evidence to determine authenticity and relevance. A recording only solves whether something can be proven; whether you should actually file a lawsuit and how long it will take must be calculated separately. For materials that should be saved before resigning, see item 8 of section 19 (Save your payslips and attendance records before resigning). All the above bases are civil litigation rules; there are separate regulations on how evidence is used in criminal and administrative cases in China.