When first introduced, the systems approach was regarded not just as a conceptual framework, but also as a symbol of unification that would promote the incipient power and influence of the social work profession. Here it needs to be noted that the approach was introduced at an early stage of development of the new monolithic social services departments and of ‘integrated’ social work training (i. e. CQSW) courses. These developments required some common, unifying principles to underpin the methods of service delivery of the new ‘generic’ social workers. Such principles were articulated in a variety of publications on unitary approaches. Not all unitary perspectives used systems theory for underpinning, however, and certainly there has never been any wholesale and uncritical adoption by social work training of either a systems or a unitary approach.