<p>When Otto Fenichel died suddenly at age 48 Anna Freud mourned the loss of &quot;his inexhaustible knowledge of psychoanalysis and his inimitable way of organizing and presenting his facts.&quot; These qualities shine in his classic text which has been a beacon to generations of psychoanalysts. Investigating the relationship between biological needs and external influences the tensions and inhibitions that nurture neuroses Fenichel concludes that &quot;neuroses are social diseases&quot; arising from the demands of civilization on the developing organism. For this 50th anniversary edition distinguished psychoanalyst Leo Rangell has written an introduction to set the context of Fenichel&#39;s work and an epilogue to describe its influence.&quot;</p>