At the beginning of this study it was said that a definition of social work was in demand for practical use. We have developed a definition which seems to hold good as far as it goes. We have said that social work includes all voluntary attempts to extend benefits in response to a need, which are concerned with social relationships and which avail themselves of scientific knowledge and employ scientific methods. It remains to test whether this is sufficiently descriptive and sufficiently definitive to be of any practical use. Is it inclusive enough to allow social work to claim all its legitimate functions and exclusive enough to rescue it from unreasonable demands? These things can only be tested by trying it out in discussion. It is therefore the purpose of this chapter to attempt such a trial by assuming that social work is no more and no less than the definition indicates and requiring it, on this representation, to run the gauntlet of familiar criticism. Up to the present time social work has not been the subject of much serious analytical comment. It has been too inchoate for that. But a sort of guerilla warfare of criticism pursues it in private conversation, on public platforms and in the obiter dicta of current literature. The criticisms are of three principal sorts, those which say that what it does is somehow unworthy, those which say it does too much and those which say it does too little; or, more fully stated, those which charge it with an unwholesome interest in wanting to play providence to other people, those which think it is attempting something in defiance of the laws of nature and those which scorn it for tinkering with abuses which should be fallen upon and annihilated.