In his recent discussion paper in this journal, Truls Gjestland attempts a "systematic review", as he calls it, of the evidence base for aircraft noise annoyance, consolidated in a meta-analysis by Guski et al. that informed the recommended guideline value of 45 dB Lden in the recently published World Health Organization (WHO) Environmental Noise Guidelines. He questions the validity of the presented evidence, as "some of the referenced studies have not been conducted according to standardized methods, and the selection of respondents is not representative of the general airport population." Gjestland maintains that the new WHO Guidelines are based on a questionable selection of existing aircraft noise studies. Our reply comments on the arguments of Gjestland and refutes most of his critique.