Cognitive approaches - For unhelpful thoughts and beliefs:

CBT

Considers that thinking, feeling and actions work together with thoughts determining behaviour and emotions.  Clients are taught how to identify distorted thoughts and how to challenge and change them.

It has been effective in treating depression and anxiety.

REBT

General and irrational beliefs are identified and challenged as necessary.  Therapy treatments work towards developing new thought processes and new values - replacing them with more useful ones.

This can be particularly helpful with; anxiety, lack of assertiveness, guilt, habit change, hurt and jealousy.  It can also be helpful with removing phobias, smoking and some weight management.