At its crudest, any attempt to control, influence or manage a candidate or client through a recruitment or sales process is likely to be seen as manipulative and self-serving.  Knowing good technique is one thing, but unless you have the right relationship with candidates and clients, you are unlikely to be able to apply it sensibly.  So make sure that your primary focus is on developing a strong relationship with each party – this ensures that when we do come to exert control, it is more likely to be effective and appropriate.