Thephenomenonofparticleinteractioninvolvedinpulmonarydrugdeliverybelongstoawidevarietyofdisciplinesofparticletechnology,inparticular,fluidization.Thispaperreviewsthebasicconceptsofpulmonarydrugdeliverywithreferencestofluidizationresearch,inparticular,studiesonGeldartgroupCpowders.Drypowderinhalerdevice-formulationcombinationhasbeenshowntobeaneffectivemethodfordeliveringdrugstothelungfortreatmentofasthma,chronicobstructivepulmonarydiseaseandcysticfibrosis.Evenwithadvanceddesigns,however,deliveryefficiencyisstillpoormainlyduetopowderdispersionproblemswhichcausepoorlungdepositionandhighdosevariability.Drugparticlesusedincurrentinhalersmustbe1-5mindiameterforeffectivedepositioninsmall-diameterairwaysandalveoli.Thesepowdersareverycohesive,havepoorflowability,andaredifficulttodisperseintoaerosolduetocohesionarisingfromvanderWaalsattraction.Theseproblemsarewellknowninfluidizationresearch,muchofwhichishighlyrelevanttopulmonarydrugdelivery.