Single-wall carbon nanotubes (SWNTs) are well dispersed in water using a polymer, polyvinylpyrrolidone (PVP), a surfactant, sodium dodecyl benzene sulfonate (SDBS), and brief low-power sonication. The concentration of these pristine SWNT dispersions are quite high, approaching 1 g/L, and remain stable over several months. These suspensions can be used as a printable conductive material and were used to create novel self-assembled SWNT arrays which are highly aligned. Suspensions of pristine SWNTs in water enable their application to aqueous chemistry, reduce environmental impact from use of organic solvents, and create suspensions which are compatible with materials sensitive to harsh solvents. Avoiding covalent functionalization allows for the SWNTs to have optimum mechanical and electronic properties and maintain lengths of several micrometers.