Pharmaceutical proteins and peptides have become more and more important therapeutic agents to improve the quality of life of patients.However,these drugs are either enzymatically unstable or impermeable.The effective delivery of peptide and protein drugs remains a major challenge.Enabling formulation approaches are highly in demand for successful delivery of these pharmaceutical peptides and proteins.Micro/nanoparticulate systems may provide protein and peptide drugs with a few functionalities,e.g.extended effects,improved stability,enhanced bioavailability and reduced side effects.In particular,micro/nanoparticles in dry forms are very attractive because peptide and protein drugs are more stable in the solid state than in the liquid state.This manuscript aims to review current state of the art in particle engineering technologies enabling effective delivery of peptide and protein drugs by formulating them into solid forms.