Indoor localisation methods can be divided into two categories: (1) range-based localisation methods where a model between the received signal power and the communication distance is applied; and (2) range-free localisation methods where a fingerprint database is required. The Wi-Fi signal strengths in indoor environments would be affected by various time-varying environmental factors (e.g. number of people, humidity and temperature). To tackle this problem, Dr Lu proposed one method in each category for wireless localisation in time-varying indoor environments. Both proposed methods give better localisation accuracy.