`The facts are friendly': research evidence indicates that person-centred therapy is effective and at least as effective as other modalities

There is research evidence for the ef®cacy and ef®ciency of person-centred therapy. Although this has been there from the very start of the approach, the most relevant and persuasive of this evidence dates from the 1990s onwards. In his review of recently published outcome research studies Bozarth (1998: 172±173) found no evidence that speci®c treatments are effective for speci®c dysfunctions but that it is the quality of the relationship between therapist and client which is signi®cant. This he understood to include the necessary and suf®cient conditions.