At a time when the credibility of social work is again being questioned this book offers a critical approach to the debate concerning the reliability & validity of the evidence research & knowledge that underpins professional social work practice. It critiques the notion of 'evidence' & argues that 'knowledge' is a much broader more appropriate concept to consider. There is analysis of the different components & sources of this knowledge & an exploration of the often discordant interface between practice & knowledge. Finally it supports the view that knowledge can be actively developed & tested by a range of people.