Hard to explain...a pc counsellor offers counselling on pretty much any possible issue, but unlike other forms of counselling, it is not directive, we don't give advice. Instead it is based on Carl Rogers' theory that every individual has an inate actualising tendency and will strive towards becoming a fully functioning person, however, conditions of worth, negative self-concepts, a need for positive regard from others, etc get in the way. So, rather than giving clients the answers, you help them to find their own answers by offering the core conditions (the three main ones being empathy, congruence and unconditional positive regard). Unlike CBT and others it is not a quick fix, but it does work for a lot of people and allows them to go at their own pace.
Not sure if that makes any more sense, and there is a lot more to it, but it would take at least a lenghty essay to explain it all....