This page provides you with some links for you to get a flavor for the evidence base of the approaches I use for counseling.
The effectiveness of counselling, in general, is well established. Here is a link to one of the early meta-analyses looking at summarizing the findings of many (over 300) studies.
This study looks at how these approaches compare to one another in effectiveness. Generally, approaches are going to vary in suitability according to presentation(symptoms) and individual differences. Often a unique, integrative, treatment plan is suggested.