The growing number of mountaineers (climbers and trekkers) makes the problem of human waste amount to a considerable size (in tonnes of faeces and cubic metres of urine) of environmental degradation. Purity in the high mountains depends mainly on the mountaineers visiting them (the rule of ‘Leave No Trace’); however, if there is no assured suitable sanitation system, no mountaineer can be blamed for leaving human waste (faeces and urine), because the process of excretion cannot be stopped. The management can address the issue in three ways: complete (non–invasive), partial (superficial), and invasive. Those approaches have been elaborately explained in three case studies: Fuji–san (Japan), Yamunotri (India) and Kilimanjaro (Tanzania), respectively. Each of the places have been described based on the provided human waste disposal solutions, starting from the historical perspective and ending with the plans for future implementations, i.e. how it was, how it is, and how it will be. The results showed the improvement of understanding of the environmental pollution by human waste, at least from the management site. Decent changes have appeared in recent years–management bodies care more about human waste disposal. The authorities of mountain regions are gradually exchanging the old, leaking toilets for brand–new eco–friendly ones. Even if this process is slow–mostly because of economical limitations–management bodies appear to be noticing this threat. However, mountaineers do not always follow the implemented and recommended solution, as this study shows. The users should change their irresponsible behaviour, because even the best solutions in the case of human waste disposal in high–mountain conditions will fail if they do not follow the rules.