Atmospheric pressure ion sources such as atmospheric pressure chemical ionization(APCI), electrospray ionization (ESI)[6-8],matrix-assisted laser desorption ionization(MALDI)[9-10] and atmospheric pressure photoionization (APPI) have broadened the range of compounds that can be analyzed by mass spectrometry. However, these ion sources require that samples be exposed to elevated temperatures and electrical potentials,ultraviolet irradiation, laser radiation, or a high-velocity gas stream. Safety considerations require that the ion source be fully enclosed to protect the operator from harm. The new ion source reported herein overcomes these limitations. The new technique, referred to as Direct Analysis in Real Time(DART™), has been coupled to the AccuTOF-LC™ atmospheric pressure ionization mass spectrometer to permit high-resolution, exact mass measurements of gases, liquids, and solids[12,13]. DART successfully sampled hundreds of chemicals, including chemical agents and their signatures, pharmaceutics,metabolites, pesticides and environmentally significant compounds, peptides and oligosaccharides, synthetic organics, organometallics, drugs of abuse, explosives, and toxic industrial chemicals. These chemicals were detected on a variety of surfaces such as concrete, human skin, currency, airline boarding passes, fruits and vegetables, body fluids, cocktail glasses,and clothing. The composition of drug capsules and tablets was directly analyzed.