colleague Guo Youzhi, who also held the position of a Palace Attendant, tended to be mild-tempered and non-confrontational when dealing with people, the burden of advising the emperor Liu Shan and speaking up on difficult issues largely rested on Dong Yun's shoulders. Dong Yun performed his duties well and did his best to plan ahead and preempt problems that could possibly arise. Objecting to Liu Shan's plan to expand his harem When Liu Shan wanted to have more concubines, Dong Yun pointed out that his imperial harem was already full and reminded him that according to historical precedent a ruler should have no more than 12 women in his harem. He also firmly refused to carry out the emperor's order to search for more women to join the harem. Liu Shan, unable to get what he wanted, resented and feared Dong Yun. Rejecting a peerage Jiang Wan, the Prefect of the Masters of Writing () and Inspector of Yi Province (), once wrote a memorial to Liu Shan to express his wish to step down and let Fei Yi and Dong Yun succeed him. He also wrote: "(Dong) Yun has served in the palace for many years and done his best to support and uphold the dynasty. He should be awarded a peerage to honour him for his contributions." However, Dong Yun declined to accept a peerage. Keeping Huang Hao in check As Liu Shan grew older, he started to favour the palace eunuch Huang Hao, who actively fawned on the emperor in a concerted attempt to rise to higher positions and gain greater power in the Shu government. When Dong Yun learnt about this, he openly criticised the emperor for showing favouritism towards Huang Hao and, at the same time, severely reprimanded the eunuch for his behaviour. Huang Hao feared Dong Yun so he did not dare to cause any trouble; he also never made it to any position higher than that of an Assistant of the Yellow Gate () while Dong Yun was still alive. Treating his colleagues with respect On one occasion, when Dong Yun was about to leave his residence for a casual hang-out with his friends Fei Yi, Hu Ji and others, he heard that a junior colleague, Dong Hui (), had come to visit and consult him. After seeing that Dong Yun already had an appointment and was about to board the carriage, Dong