Anewkindofprofessionalpurchaserbentongettingrock-bottomcoststhreatenssuppliersofbasicmaterials.Butthesecompaniescansavethemselvesbytakingupthepurchasers?weaponsThereisakillerontheloosenearthestartofthevaluechain.SuppliersofbasicmaterialsHYPERLINK"http://www.mckinseyquarterly.com/"\l"foot1"1haveseentoughtimesastheirownsuppliersconsolidatedandcustomerssqueezedtheirmargins.Nowsomeofthosecustomersareusingakindofsophisticatedprofessionalpurchaser,knownasa"sourcer,"whothreatenstoruboutthemeagermarginsthatremain.Armedwithadetailedknowledgeofthesuppliers?economics,thesourcerspurnsthetraditionalapproachofbuildingcloserelationshipsinfavorofextractingthemostvalueatthelowestpossiblecost.Somesuppliersmaynotsurvivetheassault.Indeed,thismismatchcandestroyvaluequickly.Oneglobalproducerofspecialtylubricantsrecentlyacquiredseveralservicebusinessesinanefforttodistinguishitselffromcompetitors.Theinitialstrategywassound.Butthensourcersdemandedthatthesupplierbundleitsnewserviceswiththelubricantsatnoextracharge.Topreservesalesvolumes,thesupplieracquiesced.Intheend,whathadstartedasasensibleefforttocombineachemicalbusinessthathada5percentreturnonsaleswithservicebusinessesthathada15percentROSgavethecompanyanoverallROSoflessthan5percent.Somesuppliershavesufferedsomuchfromthesourcers?attacksthatcounteringthem,ratherthanpassivelywatchingmarginserodefurther,mustnowbeastrategicpriority.Afirststepisforsupplierstounderstandhowsourcershaveshiftedtheoddsagainstthem.Thesecondistousethatunderstandingbyfightingbackthroughinternalimprovementsandbytakingadvantageofthementalityofthesourcerstocreatevalueforboththemandthesuppliers.Andsuppliersmusttakeamuchtoughernegotiatingstand梚fnecessary,reducingtheirservicestocustomersorevenabandoningcustomers,howeverlong-standing,thathavebecometooexpensivetoserve.SmartstuffProfessionalsourcersfirstappearedabouttenyearsago.Initially,theytargetedretailersanddistributors;latertheymovedupthevaluechaintoincludesuppliersofbasicmaterials.Insteadoflookingforsupplierst