Unlike many trades, there is no universally recognised accreditation for fung shui practitioners, which means clients are susceptible to unscrupulous individuals who lack the adequate knowledge, training and experience. This has given fung shui a poor reputation in recent years and months. So how does one determine whether a fung shui master is genuine? Titles are not a good indication because anyone can label themselves a 'master' or even 'grand master'. A certificate of attendance in classes run by a renowned fung shui master is also not adequate because this may have been for a few sessions only. Self-proclaimed practitioners who declare they have learned the art solely from books also have credibility issues. A genuine fung shui master will readily tell you who they learned from and also specify the amount of time they spent being an apprentice to that teacher. The teacher's credentials can then be ascertained through the number of books they have published (in English or Putonghua) or by inquiring through other fung shui practitioners. Thus, a lineage may be established, but beware of those who falsely claim to be from a particular lineage. Perhaps the best indication of a fung shui master's worth can be gleaned from the client referrals he or she has accumulated. Some successful masters depend solely on word of mouth instead of marketing and advertising.